1 00:00:00,000 --> 00:00:12,060 foreign 2 00:00:30,220 --> 00:00:27,130 [Music] 3 00:00:42,580 --> 00:00:30,230 foreign 4 00:01:07,020 --> 00:00:57,120 [Music] 5 00:01:27,130 --> 00:01:07,030 foreign 6 00:01:48,590 --> 00:01:42,580 [Music] 7 00:01:48,600 --> 00:01:52,000 foreign 8 00:02:18,470 --> 00:02:00,630 [Music] 9 00:02:18,480 --> 00:02:22,010 foreign 10 00:02:22,020 --> 00:02:29,630 [Music] 11 00:02:29,640 --> 00:02:37,000 foreign 12 00:03:07,030 --> 00:02:42,560 [Music] 13 00:03:27,110 --> 00:03:07,040 foreign 14 00:03:35,590 --> 00:03:33,530 [Music] 15 00:03:45,050 --> 00:03:35,600 thank you 16 00:03:45,060 --> 00:03:48,660 foreign 17 00:04:48,530 --> 00:04:00,620 [Music] 18 00:04:57,120 --> 00:04:49,140 thank you 19 00:05:00,210 --> 00:04:58,969 [Music] 20 00:05:12,570 --> 00:05:00,220 foreign 21 00:05:46,090 --> 00:05:27,120 [Music] 22 00:05:46,100 --> 00:05:57,120 thank you 23 00:06:07,010 --> 00:06:04,790 [Music] 24 00:06:12,570 --> 00:06:07,020 foreign 25 00:06:48,469 --> 00:06:17,050 [Music] 26 00:06:48,479 --> 00:06:52,010 thank you 27 00:07:21,050 --> 00:07:00,630 [Music] 28 00:07:21,060 --> 00:07:27,130 foreign 29 00:07:27,140 --> 00:07:57,650 [Music] 30 00:07:57,660 --> 00:08:00,600 thank you 31 00:09:36,980 --> 00:08:29,170 [Music] 32 00:09:57,110 --> 00:09:36,990 foreign 33 00:10:30,210 --> 00:10:12,560 [Music] 34 00:10:42,560 --> 00:10:30,220 foreign 35 00:10:59,030 --> 00:10:51,990 [Music] 36 00:11:30,060 --> 00:11:00,620 foreign 37 00:11:30,070 --> 00:11:34,790 [Music] 38 00:11:34,800 --> 00:11:40,080 foreign 39 00:12:22,250 --> 00:11:53,720 [Music] 40 00:12:22,260 --> 00:12:25,560 foreign 41 00:13:35,930 --> 00:13:05,400 [Music] 42 00:13:35,940 --> 00:14:03,410 foreign 43 00:14:03,420 --> 00:14:48,050 [Music] 44 00:14:48,060 --> 00:15:17,420 foreign 45 00:16:10,970 --> 00:15:37,050 [Music] 46 00:16:10,980 --> 00:16:17,410 foreign 47 00:16:17,420 --> 00:17:01,370 [Music] 48 00:17:01,380 --> 00:17:12,980 thank you 49 00:17:18,559 --> 00:17:16,250 [Music] 50 00:18:00,270 --> 00:17:18,569 foreign 51 00:18:00,280 --> 00:18:09,409 [Music] 52 00:18:41,410 --> 00:18:11,800 foreign 53 00:20:41,600 --> 00:18:51,020 [Music] 54 00:20:54,670 --> 00:20:41,610 foreign 55 00:20:57,410 --> 00:20:56,210 [Music] 56 00:21:28,200 --> 00:20:57,420 foreign 57 00:21:28,210 --> 00:21:33,169 [Music] 58 00:21:33,179 --> 00:21:53,410 YouTube 59 00:23:14,300 --> 00:22:00,980 [Music] 60 00:23:20,210 --> 00:23:14,310 thank you 61 00:23:21,610 --> 00:23:20,220 [Music] 62 00:23:37,370 --> 00:23:21,620 foreign 63 00:24:39,930 --> 00:23:48,560 [Music] 64 00:25:39,049 --> 00:24:39,940 foreign 65 00:25:41,160 --> 00:25:39,059 [Music] 66 00:25:51,890 --> 00:25:41,170 thank you 67 00:27:05,960 --> 00:25:51,900 [Music] 68 00:27:36,330 --> 00:27:05,970 foreign 69 00:29:33,289 --> 00:27:49,310 [Music] 70 00:29:33,299 --> 00:29:37,540 foreign 71 00:30:39,649 --> 00:30:02,210 [Music] 72 00:30:53,770 --> 00:30:41,530 foreign 73 00:31:33,769 --> 00:31:02,910 [Music] 74 00:31:33,779 --> 00:31:50,440 thank you 75 00:32:44,690 --> 00:31:53,330 [Music] 76 00:33:25,510 --> 00:33:08,750 foreign 77 00:33:25,520 --> 00:34:01,730 [Music] 78 00:34:13,030 --> 00:34:03,230 foreign 79 00:34:13,040 --> 00:34:18,710 [Music] 80 00:34:18,720 --> 00:34:39,169 foreign 81 00:35:21,890 --> 00:35:00,550 [Music] 82 00:35:38,940 --> 00:35:31,370 foreign 83 00:36:29,030 --> 00:36:14,210 [Music] 84 00:36:29,040 --> 00:36:35,600 foreign 85 00:36:35,610 --> 00:36:53,089 [Music] 86 00:37:02,040 --> 00:36:55,100 foreign 87 00:37:02,050 --> 00:37:15,050 [Music] 88 00:37:20,329 --> 00:37:18,410 we're going to start our first talk 89 00:37:22,490 --> 00:37:20,339 session 90 00:37:26,630 --> 00:37:24,550 I hope everyone had a good breakfast 91 00:37:28,010 --> 00:37:26,640 I'm putting some more announcements I 92 00:37:30,710 --> 00:37:28,020 realized there's probably some confusion 93 00:37:32,630 --> 00:37:30,720 like the Drive Lines a little crowded so 94 00:37:34,670 --> 00:37:32,640 feel free to eat in that Courtyard area 95 00:37:35,750 --> 00:37:34,680 in the morning I posted a picture I'll 96 00:37:37,130 --> 00:37:35,760 post that where like where more 97 00:37:38,390 --> 00:37:37,140 bathrooms are it's like they're all in 98 00:37:41,089 --> 00:37:38,400 the back there but there's also two 99 00:37:43,430 --> 00:37:41,099 bathrooms that are close to Surfside 100 00:37:45,349 --> 00:37:43,440 um but anyway Let's uh get started so 101 00:37:48,950 --> 00:37:45,359 our first speaker is going to be Gage 102 00:37:57,109 --> 00:37:54,530 [Applause] 103 00:37:58,849 --> 00:37:57,119 hello everyone yeah so for those you 104 00:38:00,170 --> 00:37:58,859 have who haven't met me yet yeah my name 105 00:38:02,329 --> 00:38:00,180 is Gage and I'm going to be talking 106 00:38:04,790 --> 00:38:02,339 about assembly Theory and in particular 107 00:38:06,650 --> 00:38:04,800 strings and hopefully by the end of this 108 00:38:08,270 --> 00:38:06,660 I will have convinced you that it is 109 00:38:09,710 --> 00:38:08,280 very useful for astrobiology in 110 00:38:12,589 --> 00:38:09,720 particular 111 00:38:14,270 --> 00:38:12,599 so in assembly Theory the primary 112 00:38:16,550 --> 00:38:14,280 quantity we're concerned with is called 113 00:38:18,410 --> 00:38:16,560 assembly index and it's a complexity 114 00:38:19,910 --> 00:38:18,420 measure that corresponds to the minimal 115 00:38:23,270 --> 00:38:19,920 number of joining operations that it 116 00:38:26,210 --> 00:38:23,280 takes to build an object so if my object 117 00:38:27,530 --> 00:38:26,220 is like X and I need at least three of 118 00:38:29,810 --> 00:38:27,540 these steps where I combine two things 119 00:38:32,210 --> 00:38:29,820 to make something new to get to X from 120 00:38:34,550 --> 00:38:32,220 some set of fundamental building blocks 121 00:38:35,630 --> 00:38:34,560 then we said the assembly index of X is 122 00:38:38,089 --> 00:38:35,640 three 123 00:38:39,589 --> 00:38:38,099 and so 124 00:38:41,210 --> 00:38:39,599 assembly index is kind of system 125 00:38:43,370 --> 00:38:41,220 dependent in much the same way that 126 00:38:44,870 --> 00:38:43,380 entropy is where for entropy I get to 127 00:38:47,089 --> 00:38:44,880 choose what my micro and macro states 128 00:38:49,010 --> 00:38:47,099 are and this influences exactly what it 129 00:38:50,569 --> 00:38:49,020 means and for assembly index these 130 00:38:52,430 --> 00:38:50,579 things that we get to choose are what 131 00:38:54,530 --> 00:38:52,440 our fundamental building blocks are and 132 00:38:56,930 --> 00:38:54,540 what the different joining operations 133 00:38:58,730 --> 00:38:56,940 that are allowable are 134 00:39:01,010 --> 00:38:58,740 and so 135 00:39:02,630 --> 00:39:01,020 we 136 00:39:04,790 --> 00:39:02,640 kind of philosophically what this thing 137 00:39:07,490 --> 00:39:04,800 means is that if I find some really 138 00:39:09,170 --> 00:39:07,500 complex object let's call it a and it 139 00:39:11,990 --> 00:39:09,180 has an assembly index of 140 00:39:14,150 --> 00:39:12,000 n and I find lots of copies of this 141 00:39:16,849 --> 00:39:14,160 object I can be sure that somewhere in 142 00:39:18,710 --> 00:39:16,859 the environment there's at least some 143 00:39:20,990 --> 00:39:18,720 end construction processes that exists 144 00:39:22,130 --> 00:39:21,000 there that memory is stored somewhere in 145 00:39:24,470 --> 00:39:22,140 the environment that's creating these 146 00:39:26,089 --> 00:39:24,480 objects and that just simply has to be 147 00:39:29,450 --> 00:39:26,099 true because 148 00:39:30,890 --> 00:39:29,460 for objects even as small as like modest 149 00:39:32,810 --> 00:39:30,900 size proteins there's not enough like 150 00:39:35,089 --> 00:39:32,820 matter on Earth to make all of them in 151 00:39:36,710 --> 00:39:35,099 any kind of meaningful abundance 152 00:39:39,109 --> 00:39:36,720 and so 153 00:39:41,150 --> 00:39:39,119 this approach kind of lives between two 154 00:39:43,130 --> 00:39:41,160 different worlds so one is like 155 00:39:44,750 --> 00:39:43,140 you know I might want to know the 156 00:39:46,609 --> 00:39:44,760 explicit physics or chemistry that's 157 00:39:48,050 --> 00:39:46,619 going on and know exactly how these 158 00:39:49,790 --> 00:39:48,060 things are actually built every time and 159 00:39:52,010 --> 00:39:49,800 understand those pathways 160 00:39:53,810 --> 00:39:52,020 but in assembly Theory we just take 161 00:39:55,430 --> 00:39:53,820 what's the minimal like hypothetical 162 00:39:57,230 --> 00:39:55,440 thing that we can't rule out as 163 00:39:58,490 --> 00:39:57,240 impossible and this is a massive 164 00:39:59,750 --> 00:39:58,500 simplification so we don't have to 165 00:40:01,609 --> 00:39:59,760 understand all the microphysical 166 00:40:04,130 --> 00:40:01,619 properties but we can still put lower 167 00:40:05,329 --> 00:40:04,140 bounds on how much it can take to make 168 00:40:07,910 --> 00:40:05,339 these objects 169 00:40:09,170 --> 00:40:07,920 on the other end of the spectrum it kind 170 00:40:12,650 --> 00:40:09,180 of varies from algorithmic information 171 00:40:14,329 --> 00:40:12,660 Theory where I would instead say you 172 00:40:16,550 --> 00:40:14,339 know something is so simple based off of 173 00:40:18,470 --> 00:40:16,560 how small of a program I can write that 174 00:40:19,970 --> 00:40:18,480 creates it in a computer language but in 175 00:40:21,829 --> 00:40:19,980 assembly Theory we're requiring it every 176 00:40:25,250 --> 00:40:21,839 step that that everything that's 177 00:40:26,990 --> 00:40:25,260 happening is physically possible 178 00:40:30,410 --> 00:40:27,000 and so 179 00:40:32,210 --> 00:40:30,420 strings are biologically relevant as we 180 00:40:33,470 --> 00:40:32,220 are all probably quite familiar with it 181 00:40:35,329 --> 00:40:33,480 can be encoded in like two different 182 00:40:38,569 --> 00:40:35,339 alphabets so I can write it in like 183 00:40:42,410 --> 00:40:38,579 nucleotides or in amino acids 184 00:40:44,990 --> 00:40:42,420 and like many other fields of physics 185 00:40:46,670 --> 00:40:45,000 setting strings is like studying 186 00:40:48,410 --> 00:40:46,680 symmetries and so this is kind of a 187 00:40:50,270 --> 00:40:48,420 diagram here of this top string of where 188 00:40:52,370 --> 00:40:50,280 different symmetric sub strings are 189 00:40:54,589 --> 00:40:52,380 within it and when you look at this 190 00:40:56,270 --> 00:40:54,599 these correspond to meaningful 191 00:40:58,730 --> 00:40:56,280 properties in the ways you can build it 192 00:41:01,970 --> 00:40:58,740 in the shortest paths so 193 00:41:04,430 --> 00:41:01,980 one feature I want to point out is that 194 00:41:06,650 --> 00:41:04,440 so in this bottom left bit here I have 195 00:41:08,630 --> 00:41:06,660 this one two segment that I'm doubling 196 00:41:10,730 --> 00:41:08,640 with itself into one two one two and we 197 00:41:12,109 --> 00:41:10,740 call this kind of innovation-like and 198 00:41:13,910 --> 00:41:12,119 then it's like I have the blueprints for 199 00:41:16,790 --> 00:41:13,920 it and I don't need to rebuild it from 200 00:41:19,190 --> 00:41:16,800 scratch every time 201 00:41:20,569 --> 00:41:19,200 so this has a lot of really nice 202 00:41:22,670 --> 00:41:20,579 mathematical properties and it's a 203 00:41:25,190 --> 00:41:22,680 really rich subject so like 204 00:41:26,750 --> 00:41:25,200 this thing on the bottom looks like like 205 00:41:29,210 --> 00:41:26,760 ice cream with sprinkles in it but it's 206 00:41:31,370 --> 00:41:29,220 it's it's a some kind of weird graph 207 00:41:32,870 --> 00:41:31,380 which actually corresponds to like how 208 00:41:35,329 --> 00:41:32,880 you reconcile all these symmetries 209 00:41:37,190 --> 00:41:35,339 together to calculate like what the 210 00:41:38,569 --> 00:41:37,200 shortest build path is and it has a 211 00:41:40,550 --> 00:41:38,579 really nice relation to some like really 212 00:41:42,710 --> 00:41:40,560 classic problems in computation theory 213 00:41:44,810 --> 00:41:42,720 that tell us about how complicated it is 214 00:41:47,390 --> 00:41:44,820 to calculate these things 215 00:41:50,329 --> 00:41:47,400 um but much more Salient to astrobiology 216 00:41:52,970 --> 00:41:50,339 is thinking about uh 217 00:41:55,609 --> 00:41:52,980 what we could call Prime strings or I 218 00:41:57,230 --> 00:41:55,619 would argue also materially efficient 219 00:41:59,930 --> 00:41:57,240 techno signatures 220 00:42:01,550 --> 00:41:59,940 so the example I want to kind of 221 00:42:02,930 --> 00:42:01,560 describe this as is it's just a series 222 00:42:05,450 --> 00:42:02,940 of numbers but what would it mean in 223 00:42:09,230 --> 00:42:05,460 maybe a material is if I restrict myself 224 00:42:10,910 --> 00:42:09,240 to working with polymer chains and my 225 00:42:13,130 --> 00:42:10,920 alphabet size is basically how many 226 00:42:16,130 --> 00:42:13,140 different monomers I have access to 227 00:42:18,349 --> 00:42:16,140 if I want to find how do I efficiently 228 00:42:19,490 --> 00:42:18,359 create something that demonstrates I 229 00:42:20,690 --> 00:42:19,500 know how to compute a lot of different 230 00:42:23,150 --> 00:42:20,700 reactions 231 00:42:25,190 --> 00:42:23,160 then I need something that has as few 232 00:42:26,630 --> 00:42:25,200 symmetries in it as possible and there's 233 00:42:28,010 --> 00:42:26,640 actually really explicit ways to 234 00:42:32,690 --> 00:42:28,020 construct these things such that they 235 00:42:34,310 --> 00:42:32,700 have absolutely no I I can construct 236 00:42:36,170 --> 00:42:34,320 there's many different ways to build 237 00:42:38,630 --> 00:42:36,180 these strings but none of them reuse the 238 00:42:40,069 --> 00:42:38,640 exact same reaction twice by virtue of 239 00:42:41,750 --> 00:42:40,079 just what they are 240 00:42:43,010 --> 00:42:41,760 and that's a property introduced to 241 00:42:44,569 --> 00:42:43,020 these objects and this also kind of 242 00:42:46,430 --> 00:42:44,579 highlights the difference between this 243 00:42:47,750 --> 00:42:46,440 and algorithmic information Theory 244 00:42:50,270 --> 00:42:47,760 because like 245 00:42:52,069 --> 00:42:50,280 if I asked anybody to like make the next 246 00:42:53,150 --> 00:42:52,079 one you'd probably all get it right on 247 00:42:54,589 --> 00:42:53,160 the first try there's a lot of 248 00:42:56,030 --> 00:42:54,599 regularity in what these objects look 249 00:42:57,710 --> 00:42:56,040 like and so algorithmically they're not 250 00:42:59,089 --> 00:42:57,720 that complicated but in terms of the 251 00:43:02,390 --> 00:42:59,099 physical reactions you need to make them 252 00:43:07,609 --> 00:43:03,910 so 253 00:43:09,710 --> 00:43:07,619 future and that what I'm really excited 254 00:43:12,290 --> 00:43:09,720 to do with this is have a dynamics of 255 00:43:14,450 --> 00:43:12,300 how life can explore the chemical space 256 00:43:16,490 --> 00:43:14,460 of what's possible 257 00:43:18,470 --> 00:43:16,500 and so the picture I want to illustrate 258 00:43:20,390 --> 00:43:18,480 these are not real data this is just to 259 00:43:24,109 --> 00:43:20,400 illustrate a point is I want to think 260 00:43:26,390 --> 00:43:24,119 about some space of objects and I think 261 00:43:29,089 --> 00:43:26,400 a good example is all the proteins that 262 00:43:30,890 --> 00:43:29,099 a species creates say so we take all 263 00:43:32,750 --> 00:43:30,900 these proteins and I want to assign 264 00:43:35,030 --> 00:43:32,760 distances between them all and 265 00:43:36,109 --> 00:43:35,040 qualitatively I mean there's an example 266 00:43:38,630 --> 00:43:36,119 of how to do that on the top but 267 00:43:41,870 --> 00:43:38,640 qualitatively what we should think of is 268 00:43:44,150 --> 00:43:41,880 the distance between X and Y is the 269 00:43:46,130 --> 00:43:44,160 number of joining operations that I need 270 00:43:48,050 --> 00:43:46,140 to change to go from one to the other 271 00:43:49,609 --> 00:43:48,060 and so things that are intuitively 272 00:43:53,690 --> 00:43:49,619 similar will be closer 273 00:43:55,430 --> 00:43:53,700 and just yeah as you might expect and so 274 00:43:56,290 --> 00:43:55,440 this is really useful because when we 275 00:43:59,150 --> 00:43:56,300 think about 276 00:44:01,130 --> 00:43:59,160 what we have as a generative model for 277 00:44:03,890 --> 00:44:01,140 like a null hypothesis like what should 278 00:44:05,930 --> 00:44:03,900 life be doing we know that mutations are 279 00:44:07,849 --> 00:44:05,940 things that really only change assembly 280 00:44:09,650 --> 00:44:07,859 index by one either I'm inserting some 281 00:44:10,609 --> 00:44:09,660 large segment that already existed and 282 00:44:12,290 --> 00:44:10,619 so I didn't have to build it from 283 00:44:14,990 --> 00:44:12,300 scratch or I'm making some really small 284 00:44:17,870 --> 00:44:15,000 change and in any case this is a very a 285 00:44:20,150 --> 00:44:17,880 change in assembly index of just one 286 00:44:22,250 --> 00:44:20,160 and so we have this kind of 287 00:44:24,410 --> 00:44:22,260 thick surface of the adjacent possible 288 00:44:27,050 --> 00:44:24,420 like things you can mutate into and 289 00:44:28,970 --> 00:44:27,060 because it's reasonable to imagine that 290 00:44:31,250 --> 00:44:28,980 this is happening kind of randomly 291 00:44:33,170 --> 00:44:31,260 we can have some kind of no model for 292 00:44:35,390 --> 00:44:33,180 what we expect life to look like like 293 00:44:37,130 --> 00:44:35,400 what's the shape of this object as it 294 00:44:38,630 --> 00:44:37,140 grows in time 295 00:44:40,609 --> 00:44:38,640 and 296 00:44:42,230 --> 00:44:40,619 so I like to think of it as kind of 297 00:44:44,210 --> 00:44:42,240 spherical but actually it's probably a 298 00:44:45,109 --> 00:44:44,220 little bit noisy just because it is so 299 00:44:46,790 --> 00:44:45,119 Random 300 00:44:48,650 --> 00:44:46,800 but in reality I don't think we'll 301 00:44:50,270 --> 00:44:48,660 really observe this because some 302 00:44:52,309 --> 00:44:50,280 mutations will be selected out and we'll 303 00:44:54,230 --> 00:44:52,319 never observe them and so the way I want 304 00:44:56,569 --> 00:44:54,240 to illustrate this is this you have this 305 00:44:58,970 --> 00:44:56,579 kind of noisy sphere on the left and you 306 00:45:01,730 --> 00:44:58,980 have a much noisier version of it on the 307 00:45:03,770 --> 00:45:01,740 right and you know if I observe this for 308 00:45:05,329 --> 00:45:03,780 two different things the interpretation 309 00:45:07,370 --> 00:45:05,339 of this is we're seeing something about 310 00:45:09,170 --> 00:45:07,380 like the fitness landscape like this is 311 00:45:11,809 --> 00:45:09,180 kind of the shadow that makes it through 312 00:45:13,849 --> 00:45:11,819 right so like there's lots of voids here 313 00:45:18,410 --> 00:45:13,859 of things that are either not functional 314 00:45:20,750 --> 00:45:18,420 or even hurtful to the system and 315 00:45:22,670 --> 00:45:20,760 by studying like the geometry of these 316 00:45:23,990 --> 00:45:22,680 kinds of objects and looking for the 317 00:45:27,349 --> 00:45:24,000 ways they scale we can learn things 318 00:45:29,690 --> 00:45:27,359 about the ergonicity of life meaning 319 00:45:31,030 --> 00:45:29,700 if I were to restart us from like early 320 00:45:33,050 --> 00:45:31,040 Earth times 321 00:45:35,210 --> 00:45:33,060 how similar would I expect the 322 00:45:37,490 --> 00:45:35,220 biochemistry to be today that we observe 323 00:45:38,690 --> 00:45:37,500 just by virtue of how many ways does it 324 00:45:41,210 --> 00:45:38,700 seem like there are to actually move in 325 00:45:43,130 --> 00:45:41,220 this plate in this space and by 326 00:45:45,710 --> 00:45:43,140 extension we can make inferences about 327 00:45:48,530 --> 00:45:45,720 just life in general and how 328 00:45:52,010 --> 00:45:48,540 constricted it must be and how diverse 329 00:45:55,069 --> 00:45:52,020 will potential alien biochemistries be 330 00:45:57,890 --> 00:45:55,079 so with that I'll leave you with a 331 00:46:01,170 --> 00:45:57,900 fractal that reminds me of the building 332 00:46:15,530 --> 00:46:01,180 process and I'll take any questions 333 00:46:21,430 --> 00:46:19,309 so how can this be employed to sort of 334 00:46:23,690 --> 00:46:21,440 create a Criterion for what constitutes 335 00:46:24,950 --> 00:46:23,700 abiogenesis based off the assembly 336 00:46:28,130 --> 00:46:24,960 complexes 337 00:46:29,930 --> 00:46:28,140 so there is an excellent nature comes 338 00:46:32,809 --> 00:46:29,940 paper I want to say from 2020 that's 339 00:46:34,910 --> 00:46:32,819 Marshall's the first author uh where 340 00:46:37,569 --> 00:46:34,920 they talk about so you can do this for 341 00:46:39,670 --> 00:46:37,579 molecules and they find a really big 342 00:46:41,809 --> 00:46:39,680 disparity between what kinds of things 343 00:46:44,329 --> 00:46:41,819 abiotic sources can produce versus 344 00:46:46,250 --> 00:46:44,339 biotic and this is something that you 345 00:46:48,710 --> 00:46:46,260 can measure quite accurately with like 346 00:46:51,650 --> 00:46:48,720 Mass Spec and some other methods too and 347 00:46:54,109 --> 00:46:51,660 so it just for a chemical biosignature 348 00:47:00,890 --> 00:46:54,119 way there's a concrete I think that 349 00:47:04,670 --> 00:47:03,170 hi um great talk and also just curious 350 00:47:06,890 --> 00:47:04,680 when you're evaluating the assembly 351 00:47:08,210 --> 00:47:06,900 theory is this based off of entirely the 352 00:47:11,089 --> 00:47:08,220 sequence or do you also account for 353 00:47:13,550 --> 00:47:12,710 I don't like protein folding or 354 00:47:16,730 --> 00:47:13,560 something 355 00:47:18,589 --> 00:47:16,740 ah yes so this is kind of embedded in 356 00:47:20,030 --> 00:47:18,599 like our choice of the definition of the 357 00:47:21,470 --> 00:47:20,040 joining operation right so like the 358 00:47:23,630 --> 00:47:21,480 simplest Choice doesn't count the 359 00:47:25,190 --> 00:47:23,640 protein folding but you can imagine that 360 00:47:26,870 --> 00:47:25,200 I Define the joining operations such 361 00:47:29,930 --> 00:47:26,880 that I allow myself to consider those 362 00:47:32,450 --> 00:47:29,940 like high order constructions and so 363 00:47:41,870 --> 00:47:32,460 yeah it's a choice of your 364 00:47:46,130 --> 00:47:44,270 uh yeah this is very interesting I'm 365 00:47:47,569 --> 00:47:46,140 wondering how do you consider the 366 00:47:48,829 --> 00:47:47,579 starting amino acids you have because 367 00:47:50,510 --> 00:47:48,839 there's a lot of theories on like what 368 00:47:52,190 --> 00:47:50,520 amino acids were like first or like 369 00:47:53,569 --> 00:47:52,200 which evolved later and like are you 370 00:47:55,370 --> 00:47:53,579 only using the canonical ones that we 371 00:47:57,470 --> 00:47:55,380 have in like the current genetic code or 372 00:48:00,890 --> 00:47:57,480 like they're any like theoretical amino 373 00:48:07,069 --> 00:48:02,870 I'm not uh there's someone at your table 374 00:48:10,790 --> 00:48:07,079 who does his name's Thomas 375 00:48:12,170 --> 00:48:10,800 um but I to to relate it to this I think 376 00:48:13,849 --> 00:48:12,180 this is kind of embedded in your choice 377 00:48:25,309 --> 00:48:13,859 of like what the fundamental building 378 00:48:25,319 --> 00:48:29,450 any other questions for Gage 379 00:48:39,410 --> 00:48:31,410 okay let's go around the pause 380 00:48:40,730 --> 00:48:39,420 [Applause] 381 00:48:42,470 --> 00:48:40,740 okay 382 00:48:45,530 --> 00:48:42,480 and our next speaker is going to be Alex 383 00:48:47,809 --> 00:48:45,540 Plum here from UCSD 384 00:48:49,910 --> 00:48:47,819 hi there I'm Alex Plum my talk is on 385 00:48:52,370 --> 00:48:49,920 auto catalytic chemical ecosystems in 386 00:48:53,809 --> 00:48:52,380 spatial settings uh 387 00:48:55,609 --> 00:48:53,819 so I wanted to start with this quote 388 00:48:57,470 --> 00:48:55,619 from the French nationalist George 389 00:48:58,730 --> 00:48:57,480 cuvier I don't think it's a good 390 00:49:00,530 --> 00:48:58,740 definition of life but I think it 391 00:49:02,809 --> 00:49:00,540 captures one feature of life that's very 392 00:49:04,609 --> 00:49:02,819 important uh specifically this feature 393 00:49:07,130 --> 00:49:04,619 of Auto catalysis which I think is the 394 00:49:08,630 --> 00:49:07,140 central Motif for self-propagation uh 395 00:49:10,069 --> 00:49:08,640 that we see kind of all across life and 396 00:49:12,349 --> 00:49:10,079 it may have been relevant in life's 397 00:49:14,510 --> 00:49:12,359 earliest stages so we say that a process 398 00:49:16,550 --> 00:49:14,520 is auto catalytic if the products of 399 00:49:18,410 --> 00:49:16,560 that process catalyze the process itself 400 00:49:20,329 --> 00:49:18,420 here I'm going to be talking about Auto 401 00:49:22,250 --> 00:49:20,339 catalytic Cycles where you have a 402 00:49:24,170 --> 00:49:22,260 sequence of reactions that form a cycle 403 00:49:26,450 --> 00:49:24,180 such that with every turn of the cycle 404 00:49:28,250 --> 00:49:26,460 you get a stoichiometric increase in the 405 00:49:30,530 --> 00:49:28,260 number of some set of chemicals that 406 00:49:32,270 --> 00:49:30,540 we'll call member chemicals you can take 407 00:49:34,130 --> 00:49:32,280 all of the chemicals involved in an auto 408 00:49:37,130 --> 00:49:34,140 catalytic cycle and partition them into 409 00:49:38,510 --> 00:49:37,140 food chemicals into member chemicals and 410 00:49:40,250 --> 00:49:38,520 into waste chemicals based on which 411 00:49:41,990 --> 00:49:40,260 sides of the reactions they show up in 412 00:49:44,210 --> 00:49:42,000 and so here's a simple example where you 413 00:49:46,670 --> 00:49:44,220 just have two reversible reactions you 414 00:49:48,650 --> 00:49:46,680 have two member chemicals M1 and M2 you 415 00:49:51,770 --> 00:49:48,660 have one food that's being used for both 416 00:49:53,329 --> 00:49:51,780 reactions and waste chemical and in 417 00:49:55,670 --> 00:49:53,339 principle these can be irreversible here 418 00:49:58,130 --> 00:49:55,680 I've drawn them as reversible and 419 00:50:00,650 --> 00:49:58,140 because they're reversible you can drive 420 00:50:02,210 --> 00:50:00,660 them in either direction if you have an 421 00:50:03,710 --> 00:50:02,220 abundance of food they can be driven in 422 00:50:05,450 --> 00:50:03,720 the productive direction that provides 423 00:50:06,589 --> 00:50:05,460 the stoichiometric increase in the 424 00:50:08,569 --> 00:50:06,599 member chemicals allowing them to 425 00:50:10,550 --> 00:50:08,579 self-propagate but if instead you have 426 00:50:12,109 --> 00:50:10,560 an accumulation of waste it can kind of 427 00:50:13,730 --> 00:50:12,119 wind down in the other direction and you 428 00:50:17,089 --> 00:50:13,740 can get a stoichiometric decrease in the 429 00:50:19,670 --> 00:50:17,099 number of member chemicals as well 430 00:50:21,710 --> 00:50:19,680 so we've analogized these Auto catalytic 431 00:50:22,970 --> 00:50:21,720 Cycles to biological species in part 432 00:50:24,470 --> 00:50:22,980 because they're consuming food they're 433 00:50:26,089 --> 00:50:24,480 producing waste and self-propagating 434 00:50:28,730 --> 00:50:26,099 themselves and we've demonstrated that 435 00:50:31,069 --> 00:50:28,740 they can exhibit logistic growth 436 00:50:32,569 --> 00:50:31,079 if you put them in a closed reactor some 437 00:50:34,190 --> 00:50:32,579 amount of food available some seed 438 00:50:36,050 --> 00:50:34,200 member species 439 00:50:38,390 --> 00:50:36,060 they can start growing and they can 440 00:50:40,010 --> 00:50:38,400 reach equilibrium concentrations but 441 00:50:41,510 --> 00:50:40,020 this isn't of great interest in an 442 00:50:43,309 --> 00:50:41,520 origins of Life context because life 443 00:50:44,990 --> 00:50:43,319 isn't out of equilibrium process so in 444 00:50:47,630 --> 00:50:45,000 practice we typically simulate these 445 00:50:49,970 --> 00:50:47,640 cycles and chemostats when you have an 446 00:50:51,770 --> 00:50:49,980 inflow of food from a source that drives 447 00:50:53,690 --> 00:50:51,780 them in the productive or autocatalytic 448 00:50:56,569 --> 00:50:53,700 Direction and where everything is 449 00:50:58,370 --> 00:50:56,579 diluted out of the system and this has 450 00:51:00,170 --> 00:50:58,380 two implications one it helps to offload 451 00:51:02,089 --> 00:51:00,180 the waste to kind of keep it from being 452 00:51:04,010 --> 00:51:02,099 driven in the other direction and it 453 00:51:05,809 --> 00:51:04,020 also provides a selective pressure so 454 00:51:07,609 --> 00:51:05,819 that now if the cycle doesn't replicate 455 00:51:09,530 --> 00:51:07,619 or propagate its member species quickly 456 00:51:11,089 --> 00:51:09,540 enough they'll just be diluted out of 457 00:51:12,470 --> 00:51:11,099 the reactor so it's not trivial that 458 00:51:14,829 --> 00:51:12,480 these Cycles are going to persist 459 00:51:16,730 --> 00:51:14,839 anymore persistence becomes a problem 460 00:51:17,809 --> 00:51:16,740 something that they have to kind of 461 00:51:19,370 --> 00:51:17,819 achieve 462 00:51:20,930 --> 00:51:19,380 so when you simulate these you can get 463 00:51:22,130 --> 00:51:20,940 time series that looks like this plot 464 00:51:23,569 --> 00:51:22,140 over here 465 00:51:25,250 --> 00:51:23,579 where you have a depletion of food 466 00:51:26,750 --> 00:51:25,260 through time you have logistic growth in 467 00:51:28,670 --> 00:51:26,760 the concentrations of member chemicals 468 00:51:30,049 --> 00:51:28,680 here in blue and you also have a buildup 469 00:51:32,210 --> 00:51:30,059 of waste 470 00:51:33,890 --> 00:51:32,220 you can choose to simulate them using 471 00:51:35,569 --> 00:51:33,900 ordinary differential equations if 472 00:51:37,010 --> 00:51:35,579 you're in a well-mixed reactor 473 00:51:38,450 --> 00:51:37,020 and that assumes that you have large 474 00:51:40,490 --> 00:51:38,460 enough quantities that you can treat 475 00:51:42,290 --> 00:51:40,500 continuous concentrations of chemicals 476 00:51:44,150 --> 00:51:42,300 the other approach is to simulate things 477 00:51:45,950 --> 00:51:44,160 stochastically and in kind of the large 478 00:51:47,990 --> 00:51:45,960 end limit this looks very similar to The 479 00:51:49,730 --> 00:51:48,000 Continuous case but as you go to smaller 480 00:51:51,650 --> 00:51:49,740 and smaller numbers of chemicals things 481 00:51:53,210 --> 00:51:51,660 look a lot noisier and you can start to 482 00:51:55,250 --> 00:51:53,220 have more contingency in the Dynamics 483 00:51:57,290 --> 00:51:55,260 where you can have the stochastic loss 484 00:51:59,150 --> 00:51:57,300 of a single chemical or the stochastic 485 00:52:01,549 --> 00:51:59,160 dispersal of a single chemical in a new 486 00:52:03,770 --> 00:52:01,559 location changing the dynamic somewhere 487 00:52:07,309 --> 00:52:03,780 else and so in everything I show here 488 00:52:09,049 --> 00:52:07,319 I'll be taking this stochastic approach 489 00:52:11,510 --> 00:52:09,059 so that's all the Dynamics for a single 490 00:52:13,490 --> 00:52:11,520 cycle we're ultimately interested in 491 00:52:16,430 --> 00:52:13,500 combining different cycles and seeing 492 00:52:18,410 --> 00:52:16,440 how they interact ecologically so here I 493 00:52:20,809 --> 00:52:18,420 show the the member chemical 494 00:52:23,569 --> 00:52:20,819 concentrations over time or counts over 495 00:52:25,549 --> 00:52:23,579 time for the different Auto catalytic 496 00:52:27,230 --> 00:52:25,559 Cycles shown on the left here they can 497 00:52:29,150 --> 00:52:27,240 exhibit competitive exclusion 498 00:52:31,250 --> 00:52:29,160 competitive coexistence when they share 499 00:52:33,230 --> 00:52:31,260 a common food source they can also 500 00:52:35,270 --> 00:52:33,240 exhibit mutualisms wherein the food or 501 00:52:37,970 --> 00:52:35,280 the waste of one chemical serves as food 502 00:52:39,650 --> 00:52:37,980 for another Auto catalytic cycle they 503 00:52:41,329 --> 00:52:39,660 can also exhibit predation 504 00:52:42,589 --> 00:52:41,339 where in the member chemicals of one 505 00:52:44,809 --> 00:52:42,599 cycle serve as the food for another 506 00:52:46,130 --> 00:52:44,819 cycle and the Dynamics resemble those 507 00:52:47,750 --> 00:52:46,140 that you get in the lack of ultera 508 00:52:49,309 --> 00:52:47,760 equations and ecology where you can get 509 00:52:51,410 --> 00:52:49,319 both stable and damped oscillations 510 00:52:53,990 --> 00:52:51,420 predator or prey dominance or 511 00:52:56,210 --> 00:52:54,000 coexistence of the the predator and prey 512 00:52:58,069 --> 00:52:56,220 and you can also get priority effects 513 00:53:00,049 --> 00:52:58,079 wherein two cycles might mutually 514 00:53:02,870 --> 00:53:00,059 inhibit one another so that it matters 515 00:53:05,030 --> 00:53:02,880 if one cycle gets seated in a location 516 00:53:07,849 --> 00:53:05,040 first versus the other since they'll 517 00:53:09,470 --> 00:53:07,859 suppress the growth of the other cycle 518 00:53:12,349 --> 00:53:09,480 so why is this relevant to the origin of 519 00:53:14,450 --> 00:53:12,359 life we think that these Auto catalytic 520 00:53:17,390 --> 00:53:14,460 Cycles provide one of the simplest ways 521 00:53:19,730 --> 00:53:17,400 in the absence of needing compartments 522 00:53:20,990 --> 00:53:19,740 or polymer genetics to get this sort of 523 00:53:22,190 --> 00:53:21,000 self-propagation that you see in 524 00:53:24,349 --> 00:53:22,200 metabolism 525 00:53:25,549 --> 00:53:24,359 and we think that they can provide an 526 00:53:27,829 --> 00:53:25,559 Avenue for the accumulation of 527 00:53:29,930 --> 00:53:27,839 complexity to ultimately serve as 528 00:53:31,790 --> 00:53:29,940 precursors or scaffolds for later stages 529 00:53:33,410 --> 00:53:31,800 in the origin of life so as an Avenue 530 00:53:35,450 --> 00:53:33,420 for kind of increasing the chemical 531 00:53:37,190 --> 00:53:35,460 diversity that you might need to achieve 532 00:53:38,930 --> 00:53:37,200 later stages and we think that you can 533 00:53:40,309 --> 00:53:38,940 do that by taking individual Cycles 534 00:53:42,650 --> 00:53:40,319 composing them through various 535 00:53:44,030 --> 00:53:42,660 ecological interactions and then using 536 00:53:45,470 --> 00:53:44,040 the sorts of avenues that we see in 537 00:53:46,549 --> 00:53:45,480 ecology for the accumulation of 538 00:53:50,630 --> 00:53:46,559 complexity 539 00:53:52,910 --> 00:53:50,640 ecology one way is through ecological 540 00:53:54,950 --> 00:53:52,920 succession wherein you have some species 541 00:53:56,690 --> 00:53:54,960 that lay the groundwork for others to 542 00:53:58,490 --> 00:53:56,700 later succeed them you can imagine this 543 00:54:00,410 --> 00:53:58,500 in a Chemical Context where the waste or 544 00:54:02,150 --> 00:54:00,420 member chemicals enable the activation 545 00:54:04,010 --> 00:54:02,160 of new cycles that couldn't have been 546 00:54:06,290 --> 00:54:04,020 activated into those first Cycles were 547 00:54:08,329 --> 00:54:06,300 activated you also have ideas on ecology 548 00:54:09,710 --> 00:54:08,339 about how to maximize biodiversity for 549 00:54:11,990 --> 00:54:09,720 example through the intermediate 550 00:54:13,609 --> 00:54:12,000 disturbance hypothesis and finally you 551 00:54:15,049 --> 00:54:13,619 have ideas about how spatial structure 552 00:54:17,089 --> 00:54:15,059 can be relevant to the accumulation of 553 00:54:19,130 --> 00:54:17,099 complexity in ecosystems where you have 554 00:54:21,349 --> 00:54:19,140 meta ecosystems and diversity among them 555 00:54:23,030 --> 00:54:21,359 and migration between them that allows 556 00:54:25,130 --> 00:54:23,040 for recombination in the formation of 557 00:54:26,990 --> 00:54:25,140 new ecological States 558 00:54:28,130 --> 00:54:27,000 so in an origins of Life context we 559 00:54:30,710 --> 00:54:28,140 often think about these chemical 560 00:54:32,390 --> 00:54:30,720 ecosystems as persisting and spatially 561 00:54:34,609 --> 00:54:32,400 structured environment like adsorbitive 562 00:54:36,410 --> 00:54:34,619 mineral surfaces 563 00:54:37,730 --> 00:54:36,420 moving across those surfaces where 564 00:54:39,710 --> 00:54:37,740 they're effectively concentrated where 565 00:54:41,750 --> 00:54:39,720 their diffusion is effectively lowered 566 00:54:42,770 --> 00:54:41,760 and those different ecosystems might 567 00:54:46,250 --> 00:54:42,780 interact 568 00:54:48,650 --> 00:54:46,260 they might continue to coexist they 569 00:54:51,589 --> 00:54:48,660 might fuse and modify one another and so 570 00:54:53,930 --> 00:54:51,599 we wanted to understand how 571 00:54:56,030 --> 00:54:53,940 these chemical ecosystems behave in 572 00:54:57,410 --> 00:54:56,040 space so the earlier kind of ecological 573 00:54:59,270 --> 00:54:57,420 time series that I showed you were all 574 00:55:01,430 --> 00:54:59,280 in well-mixed reactors now we're going 575 00:55:03,109 --> 00:55:01,440 to consider these systems in space so 576 00:55:04,430 --> 00:55:03,119 here's an example where a cycle is 577 00:55:05,990 --> 00:55:04,440 seated in the center and diffuses 578 00:55:07,730 --> 00:55:06,000 outwards kind of spreading to new 579 00:55:09,230 --> 00:55:07,740 sources of food and of course we know 580 00:55:10,970 --> 00:55:09,240 that spatial Dynamics are important for 581 00:55:12,530 --> 00:55:10,980 auto catalytic chemical systems we have 582 00:55:14,390 --> 00:55:12,540 classic examples like the belazov 583 00:55:15,770 --> 00:55:14,400 zabatinska reaction it's out of 584 00:55:18,049 --> 00:55:15,780 equilibrium process we know that they 585 00:55:20,809 --> 00:55:18,059 can form stable patterns 586 00:55:22,430 --> 00:55:20,819 so I want to consider cases where Cycles 587 00:55:24,530 --> 00:55:22,440 mutually inhibit one another because 588 00:55:26,030 --> 00:55:24,540 getting more complex ecosystems is easy 589 00:55:27,589 --> 00:55:26,040 when there are mutualisms between the 590 00:55:29,450 --> 00:55:27,599 Cycles it's hard when you have 591 00:55:31,010 --> 00:55:29,460 inhibition between them and there are 592 00:55:32,450 --> 00:55:31,020 various ways that Cycles can inhibit one 593 00:55:34,010 --> 00:55:32,460 another for example you can have the 594 00:55:35,690 --> 00:55:34,020 waste of one cycle interfere with the 595 00:55:37,370 --> 00:55:35,700 food of another cycle or you can have 596 00:55:38,690 --> 00:55:37,380 their member species annihilate the much 597 00:55:40,010 --> 00:55:38,700 simpler example that I show in the 598 00:55:42,349 --> 00:55:40,020 bottom this is the one that I'm going to 599 00:55:43,970 --> 00:55:42,359 be working with in the subsequent slides 600 00:55:46,130 --> 00:55:43,980 so you can put these in space here I 601 00:55:47,870 --> 00:55:46,140 have a hexagonal lattice with chemicals 602 00:55:49,250 --> 00:55:47,880 reacting within each site and diffusing 603 00:55:51,109 --> 00:55:49,260 between sites 604 00:55:52,790 --> 00:55:51,119 and I'm coloring them according to the 605 00:55:54,349 --> 00:55:52,800 fraction of member species that belong 606 00:55:57,109 --> 00:55:54,359 to one of these two mutually inhibiting 607 00:56:00,589 --> 00:55:57,119 Cycles red for cycle a B for are blue 608 00:56:02,450 --> 00:56:00,599 for cycle B and with slow diffusion they 609 00:56:04,609 --> 00:56:02,460 stop interacting and just form these 610 00:56:06,530 --> 00:56:04,619 stable patches with much higher 611 00:56:08,450 --> 00:56:06,540 diffusion you can see one cycle starts 612 00:56:09,829 --> 00:56:08,460 to crowd the other out globally and we 613 00:56:11,809 --> 00:56:09,839 can look at this more systematically 614 00:56:13,790 --> 00:56:11,819 varying the diffusion of all the 615 00:56:16,609 --> 00:56:13,800 chemicals involved kind of gradually 616 00:56:19,069 --> 00:56:16,619 increasing in the low case low diffusion 617 00:56:21,589 --> 00:56:19,079 case you end up with pretty randomly 618 00:56:22,910 --> 00:56:21,599 distributed ecological outcomes and the 619 00:56:24,890 --> 00:56:22,920 very high case you end up with one 620 00:56:27,170 --> 00:56:24,900 Global winner one cycle Drive in the 621 00:56:30,890 --> 00:56:27,180 other extinct and you can look at the 622 00:56:32,930 --> 00:56:30,900 heterogeneity of chemicals across this 623 00:56:34,370 --> 00:56:32,940 hexagonal lattice and what we find is 624 00:56:35,809 --> 00:56:34,380 that in the intermediate diffusion 625 00:56:38,210 --> 00:56:35,819 regimes 626 00:56:39,890 --> 00:56:38,220 this heterogeneity is maximized 627 00:56:41,270 --> 00:56:39,900 and insofar as these Cycles are 628 00:56:42,589 --> 00:56:41,280 inhibiting one another through these 629 00:56:45,530 --> 00:56:42,599 reactions that might produce other 630 00:56:47,030 --> 00:56:45,540 chemicals that could help to provide 631 00:56:48,109 --> 00:56:47,040 support for the activation of future 632 00:56:49,730 --> 00:56:48,119 Cycles 633 00:56:51,410 --> 00:56:49,740 you don't have that sort of interaction 634 00:56:52,730 --> 00:56:51,420 in the very very low diffusion case and 635 00:56:54,770 --> 00:56:52,740 you also lose it in the height of each 636 00:56:56,450 --> 00:56:54,780 in case when one cycle is driven extinct 637 00:56:58,609 --> 00:56:56,460 and so this suggests that some 638 00:57:00,770 --> 00:56:58,619 intermediate diffusion regimes are the 639 00:57:02,870 --> 00:57:00,780 most favorable to uh kind of this 640 00:57:05,329 --> 00:57:02,880 biodiversity so to speak of these 641 00:57:07,910 --> 00:57:05,339 chemical ecosystems 642 00:57:09,230 --> 00:57:07,920 that's all with keeping these Cycles on 643 00:57:10,670 --> 00:57:09,240 an equal playing field where they have 644 00:57:12,470 --> 00:57:10,680 the same reaction kinetics and the same 645 00:57:14,569 --> 00:57:12,480 diffusion properties what I want to show 646 00:57:16,790 --> 00:57:14,579 next is when you vary the properties of 647 00:57:19,250 --> 00:57:16,800 these two cycles asymmetrically so I'm 648 00:57:21,290 --> 00:57:19,260 showing time series here on the right of 649 00:57:23,329 --> 00:57:21,300 both Cycles being seated in some Central 650 00:57:26,690 --> 00:57:23,339 site in a three by three array and they 651 00:57:29,210 --> 00:57:26,700 can diffuse outwards I make cycle a in 652 00:57:31,790 --> 00:57:29,220 Red fiercer so that it consumes 653 00:57:33,470 --> 00:57:31,800 food more quickly than cycle B and 654 00:57:35,089 --> 00:57:33,480 because of that it starts to drive cycle 655 00:57:37,549 --> 00:57:35,099 B extinct initially 656 00:57:39,170 --> 00:57:37,559 but cycle B is made faster than cycle a 657 00:57:40,910 --> 00:57:39,180 meaning that it can diffuse outward more 658 00:57:43,069 --> 00:57:40,920 quickly and access new sources of food 659 00:57:45,470 --> 00:57:43,079 and so despite initially being driven 660 00:57:48,290 --> 00:57:45,480 down it manages to dominate in these 661 00:57:49,730 --> 00:57:48,300 outer sites and eventually reinvade so 662 00:57:52,549 --> 00:57:49,740 that in the long term it ends up driving 663 00:57:54,650 --> 00:57:52,559 cycle a extinct 664 00:57:56,030 --> 00:57:54,660 and you can kind of vary these 665 00:57:58,010 --> 00:57:56,040 properties systematically and construct 666 00:57:59,690 --> 00:57:58,020 a phase diagram here I vary the relative 667 00:58:02,089 --> 00:57:59,700 fierceness and relative fastness of the 668 00:58:03,589 --> 00:58:02,099 two cycles and you find regimes in which 669 00:58:05,690 --> 00:58:03,599 either of the Cycles can be favored 670 00:58:07,370 --> 00:58:05,700 suggesting that spatial environments can 671 00:58:08,750 --> 00:58:07,380 select for new types of traits such as 672 00:58:10,730 --> 00:58:08,760 the diffusivity of these member 673 00:58:12,410 --> 00:58:10,740 chemicals once you put them in a spatial 674 00:58:14,170 --> 00:58:12,420 environment a well-mixed reactor would 675 00:58:16,730 --> 00:58:14,180 be blind to these sorts of traits 676 00:58:18,650 --> 00:58:16,740 notably you can also look at other types 677 00:58:20,510 --> 00:58:18,660 of inhibition that don't involve 678 00:58:22,190 --> 00:58:20,520 explicit chemistry you can look at 679 00:58:24,230 --> 00:58:22,200 competition for absorption sites on 680 00:58:26,390 --> 00:58:24,240 Mineral surfaces and there we find very 681 00:58:28,609 --> 00:58:26,400 similar Dynamics and I think that this 682 00:58:30,170 --> 00:58:28,619 is suggestive that something like the 683 00:58:31,849 --> 00:58:30,180 Intermediate disturbance hypothesis 684 00:58:34,190 --> 00:58:31,859 might hold even for these chemical 685 00:58:35,390 --> 00:58:34,200 ecosystems and of course in an origins 686 00:58:37,010 --> 00:58:35,400 of Life context there are lots of 687 00:58:39,589 --> 00:58:37,020 different types of disturbances that you 688 00:58:40,730 --> 00:58:39,599 could have the noise of the spatially 689 00:58:42,829 --> 00:58:40,740 structured environment that you have 690 00:58:45,170 --> 00:58:42,839 different impacts 691 00:58:47,690 --> 00:58:45,180 and so with that I'd like to acknowledge 692 00:58:49,069 --> 00:58:47,700 David Baum my undergraduate advisor at 693 00:58:50,510 --> 00:58:49,079 the University of Wisconsin-Madison and 694 00:58:52,370 --> 00:58:50,520 Chris campus my mentor and collaborator 695 00:58:53,930 --> 00:58:52,380 at the Santa Fe Institute some excellent 696 00:58:55,430 --> 00:58:53,940 grad students and postdocs including 697 00:58:57,530 --> 00:58:55,440 profile who just defended his thesis 698 00:58:58,730 --> 00:58:57,540 last week and some excellent undergrads 699 00:59:01,130 --> 00:58:58,740 that I've had the opportunity to work 700 00:59:02,809 --> 00:59:01,140 with including Gage actually you should 701 00:59:04,370 --> 00:59:02,819 be on here 702 00:59:10,549 --> 00:59:04,380 all right with that I'll take any 703 00:59:10,559 --> 00:59:21,770 at this time 704 00:59:25,670 --> 00:59:23,690 also if everyone just wants to give you 705 00:59:27,650 --> 00:59:25,680 know their name and affiliation and ask 706 00:59:29,690 --> 00:59:27,660 a question that'd be great 707 00:59:32,030 --> 00:59:29,700 hi my name is George schaible I'm from 708 00:59:34,490 --> 00:59:32,040 Montana State University and I should 709 00:59:35,510 --> 00:59:34,500 profess I am a microbiologist so 710 00:59:36,950 --> 00:59:35,520 um but that was a great talk I thought 711 00:59:39,049 --> 00:59:36,960 you did a good job breaking down for us 712 00:59:41,450 --> 00:59:39,059 uh I'm just curious when diffusion 713 00:59:43,549 --> 00:59:41,460 happens that's I think of it in like a 714 00:59:44,990 --> 00:59:43,559 three-dimensional space so you're 715 00:59:46,130 --> 00:59:45,000 showing a lot of two-dimensional right 716 00:59:47,210 --> 00:59:46,140 crafts so what does that look like in 717 00:59:49,069 --> 00:59:47,220 three dimensions 718 00:59:50,630 --> 00:59:49,079 yeah so I didn't do simulations in 719 00:59:52,910 --> 00:59:50,640 three-dimensional space in part because 720 00:59:54,950 --> 00:59:52,920 I think the most like origins of Life 721 00:59:56,450 --> 00:59:54,960 relevant spatial structures are going to 722 00:59:57,710 --> 00:59:56,460 be these two-dimensional environments I 723 00:59:59,390 --> 00:59:57,720 think the two-dimensional environments 724 01:00:00,950 --> 00:59:59,400 can help to constrain kind of the 725 01:00:03,770 --> 01:00:00,960 effective diffusion that you would have 726 01:00:05,089 --> 01:00:03,780 they can concentrate chemistry lots of 727 01:00:07,010 --> 01:00:05,099 origins of Life theories that look at 728 01:00:08,329 --> 01:00:07,020 adsorptive Mineral surfaces already so 729 01:00:10,730 --> 01:00:08,339 we were kind of committed to that sort 730 01:00:12,530 --> 01:00:10,740 of scenario and here the idea of 731 01:00:14,270 --> 01:00:12,540 intermediate diffusion being favorable 732 01:00:16,069 --> 01:00:14,280 for chemical diversity I think that 733 01:00:17,630 --> 01:00:16,079 that's further support that that's the 734 01:00:19,370 --> 01:00:17,640 type of scenario that might be important 735 01:00:21,349 --> 01:00:19,380 I think there's a quote from Gunter 736 01:00:23,630 --> 01:00:21,359 washer who kind of pioneered some of 737 01:00:24,890 --> 01:00:23,640 these ideas that we don't build planes 738 01:00:27,289 --> 01:00:24,900 in the sky we build them on the ground 739 01:00:28,849 --> 01:00:27,299 and that's for a reason 740 01:00:31,250 --> 01:00:28,859 um I just to follow up with that what 741 01:00:32,809 --> 01:00:31,260 what kind of mineral surface would you 742 01:00:34,549 --> 01:00:32,819 like consider this yeah so that kind of 743 01:00:36,589 --> 01:00:34,559 the experimental side of my group in 744 01:00:37,670 --> 01:00:36,599 undergrad we um we were using pyrite 745 01:00:39,349 --> 01:00:37,680 surfaces 746 01:00:41,390 --> 01:00:39,359 um but here we're chemically agnostic 747 01:00:51,589 --> 01:00:41,400 and we're also agnostic to the exact 748 01:00:56,089 --> 01:00:54,530 hi I'm Ellie I'm from CU Boulder and I 749 01:00:58,250 --> 01:00:56,099 was wondering so I'm mainly a lab 750 01:01:01,490 --> 01:00:58,260 chemist and I was curious if you had any 751 01:01:03,650 --> 01:01:01,500 any like personal thoughts of how you 752 01:01:05,210 --> 01:01:03,660 would want a chemist to do some of this 753 01:01:06,950 --> 01:01:05,220 work or what kind of questions you would 754 01:01:08,690 --> 01:01:06,960 want a lab chemist to do to help ground 755 01:01:10,309 --> 01:01:08,700 truth some of the modeling that you do 756 01:01:11,630 --> 01:01:10,319 because I work a lot of like mineral 757 01:01:13,370 --> 01:01:11,640 absorption and mineral facilitated 758 01:01:15,710 --> 01:01:13,380 chemistry and of course when we do a lot 759 01:01:17,569 --> 01:01:15,720 of this stuff it is an equilibrium 760 01:01:19,789 --> 01:01:17,579 reaction because you're kind of waiting 761 01:01:21,470 --> 01:01:19,799 for it to resolve to equilibrium we're 762 01:01:23,089 --> 01:01:21,480 basing our reactions on that so like how 763 01:01:25,789 --> 01:01:23,099 would you kind of design something like 764 01:01:27,829 --> 01:01:25,799 this or like theorize or like hope for 765 01:01:29,569 --> 01:01:27,839 something right so a lot of what I 766 01:01:30,770 --> 01:01:29,579 showed that in the well-mix cases we 767 01:01:31,970 --> 01:01:30,780 were working with chemostats and 768 01:01:34,010 --> 01:01:31,980 certainly chemostats are an 769 01:01:35,809 --> 01:01:34,020 experimentally kind of realizable 770 01:01:37,370 --> 01:01:35,819 approach 771 01:01:39,589 --> 01:01:37,380 um there's another side to our group 772 01:01:42,049 --> 01:01:39,599 that looked for kind of real Auto 773 01:01:43,549 --> 01:01:42,059 catalytic cycles and known chemical 774 01:01:45,589 --> 01:01:43,559 reaction networks both biotic and 775 01:01:47,750 --> 01:01:45,599 abiotic and so I think one promising 776 01:01:49,430 --> 01:01:47,760 approach is to look at how these 777 01:01:51,049 --> 01:01:49,440 chemical ecosystems might explore that 778 01:01:53,030 --> 01:01:51,059 space where you seed with one chemical 779 01:01:54,829 --> 01:01:53,040 that activates maybe a single cycle or a 780 01:01:56,870 --> 01:01:54,839 set of cycles and then through the 781 01:01:59,270 --> 01:01:56,880 addition of subsequent seeds you might 782 01:02:00,589 --> 01:01:59,280 activate kind of new cycles and so I 783 01:02:02,930 --> 01:02:00,599 think there are kind of experimental 784 01:02:04,370 --> 01:02:02,940 approaches that can be done there and I 785 01:02:07,849 --> 01:02:04,380 think people in our group are continuing 786 01:02:11,870 --> 01:02:09,650 okay hello we have a question from 787 01:02:13,910 --> 01:02:11,880 online actually so this comes from user 788 01:02:16,490 --> 01:02:13,920 Alex he's asking can you simulate 789 01:02:17,569 --> 01:02:16,500 tipping points hysteresis spatially with 790 01:02:20,630 --> 01:02:17,579 this method 791 01:02:22,670 --> 01:02:20,640 tipping points uh it's hard to ask for a 792 01:02:25,069 --> 01:02:22,680 clarification via Zoom 793 01:02:26,510 --> 01:02:25,079 okay Alex if you can hear this um please 794 01:02:39,109 --> 01:02:26,520 clarify your question and we'll come 795 01:02:43,789 --> 01:02:41,990 hi I'm Jake from UCSD um can you clarify 796 01:02:45,589 --> 01:02:43,799 why you used a stochastic process 797 01:02:47,750 --> 01:02:45,599 instead of like just a simple solving 798 01:02:50,030 --> 01:02:47,760 differential equations analytically yeah 799 01:02:52,069 --> 01:02:50,040 so you can have cases in these chemical 800 01:02:55,010 --> 01:02:52,079 ecosystems where there's kind of some 801 01:02:56,390 --> 01:02:55,020 unstable fixed point and those unstable 802 01:02:58,069 --> 01:02:56,400 fixed points you need some degree of 803 01:02:59,329 --> 01:02:58,079 stochasticity to break out of them so 804 01:03:01,789 --> 01:02:59,339 that's one reason if I just use 805 01:03:04,370 --> 01:03:01,799 deterministic simulations you could get 806 01:03:06,650 --> 01:03:04,380 stuck in those uh it's also the case 807 01:03:09,049 --> 01:03:06,660 that in ecology we're interested in lots 808 01:03:10,549 --> 01:03:09,059 of contingency and stochasticity and 809 01:03:13,010 --> 01:03:10,559 then doing lots of replicates allows you 810 01:03:16,609 --> 01:03:13,020 to explore all those contingent outcomes 811 01:03:16,619 --> 01:03:28,190 okay we have time for one more question 812 01:03:33,410 --> 01:03:31,490 hi I'm Donna from Indiana University I'm 813 01:03:36,289 --> 01:03:33,420 an ecologist by training and it was 814 01:03:38,450 --> 01:03:36,299 really interesting to see all of those 815 01:03:40,250 --> 01:03:38,460 theories that I've been trained for in 816 01:03:43,510 --> 01:03:40,260 this context 817 01:03:46,430 --> 01:03:43,520 um a psychologist we abandoned 818 01:03:49,430 --> 01:03:46,440 intermediate disturbance hypothesis 819 01:03:51,530 --> 01:03:49,440 because we haven't observed in nature 820 01:03:54,530 --> 01:03:51,540 yeah for 20 years 821 01:03:56,870 --> 01:03:54,540 I was wondering if there are ways to 822 01:03:57,589 --> 01:03:56,880 test experimentally 823 01:04:00,289 --> 01:03:57,599 um 824 01:04:04,030 --> 01:04:00,299 what do you think about that and also 825 01:04:07,430 --> 01:04:04,040 activity in four tipping points I think 826 01:04:11,049 --> 01:04:07,440 the online person mentioned you can 827 01:04:13,670 --> 01:04:11,059 probably see the signals before 828 01:04:15,549 --> 01:04:13,680 transitions like time or took increasing 829 01:04:18,370 --> 01:04:15,559 time autocorrelation 830 01:04:20,030 --> 01:04:18,380 or coefficient of variation 831 01:04:21,589 --> 01:04:20,040 absolutely thank you for the question 832 01:04:23,390 --> 01:04:21,599 yeah so I think an ecology the 833 01:04:24,890 --> 01:04:23,400 intermediate disturbance hypothesis is 834 01:04:27,470 --> 01:04:24,900 controversial and many people have 835 01:04:29,329 --> 01:04:27,480 abandoned it I think in this kind of 836 01:04:31,430 --> 01:04:29,339 modeling context it's very easy to kind 837 01:04:34,849 --> 01:04:31,440 of look for it just because we're doing 838 01:04:36,650 --> 01:04:34,859 experiments in silico and 839 01:04:38,630 --> 01:04:36,660 I think that 840 01:04:40,190 --> 01:04:38,640 if it does hold in the biological case 841 01:04:42,170 --> 01:04:40,200 certainly it holds in the chemical case 842 01:04:43,670 --> 01:04:42,180 there's a possibility that it holds in 843 01:04:44,809 --> 01:04:43,680 the chemical case and not the biological 844 01:04:46,609 --> 01:04:44,819 case 845 01:04:47,690 --> 01:04:46,619 um I think the weak version of this is 846 01:04:49,010 --> 01:04:47,700 that there are certain types of 847 01:04:50,750 --> 01:04:49,020 disturbance regimes that can be 848 01:04:52,569 --> 01:04:50,760 beneficial for chemical diversity even 849 01:04:55,250 --> 01:04:52,579 if the intermediate disturbance 850 01:04:57,530 --> 01:04:55,260 hypothesis doesn't hold at large to the 851 01:04:59,569 --> 01:04:57,540 Tipping points question I think you do 852 01:05:01,670 --> 01:04:59,579 see sort of kind of signs in the 853 01:05:03,530 --> 01:05:01,680 diffusion cases I kind of vary it you 854 01:05:05,870 --> 01:05:03,540 end up seeing sort of power loss scaling 855 01:05:08,569 --> 01:05:05,880 in the patch size sort of like you would 856 01:05:10,190 --> 01:05:08,579 see in an icing model in physics and so 857 01:05:11,569 --> 01:05:10,200 the sort of theory that looks at 858 01:05:13,490 --> 01:05:11,579 tippling points there would also apply 859 01:05:20,390 --> 01:05:13,500 here 860 01:05:30,470 --> 01:05:23,150 okay and our next speaker is going to be 861 01:05:35,270 --> 01:05:33,230 well hello everyone first of all I'd 862 01:05:36,470 --> 01:05:35,280 like to thank for the organizers from 863 01:05:39,770 --> 01:05:36,480 having me here 864 01:05:42,049 --> 01:05:39,780 and I have already experienced how great 865 01:05:44,270 --> 01:05:42,059 this community can be I can tell that 866 01:05:45,950 --> 01:05:44,280 this is really a space for all 867 01:05:49,309 --> 01:05:45,960 so 868 01:05:50,990 --> 01:05:49,319 um how many of you like chemistry here 869 01:05:52,190 --> 01:05:51,000 in the audience 870 01:05:54,289 --> 01:05:52,200 quiet 871 01:05:55,450 --> 01:05:54,299 a few people here so 872 01:05:59,390 --> 01:05:55,460 um 873 01:06:02,089 --> 01:05:59,400 I will basically follow the logic of 874 01:06:04,190 --> 01:06:02,099 this quote throughout my whole 875 01:06:05,690 --> 01:06:04,200 presentation so probably what we're what 876 01:06:08,329 --> 01:06:05,700 I am doing and what we were doing is 877 01:06:09,710 --> 01:06:08,339 wrong but some of it might be useful in 878 01:06:10,910 --> 01:06:09,720 the future 879 01:06:11,510 --> 01:06:10,920 so 880 01:06:14,470 --> 01:06:11,520 um 881 01:06:17,690 --> 01:06:14,480 amino acids amino acids as we know 882 01:06:20,950 --> 01:06:17,700 basically looking for amino acids is one 883 01:06:23,470 --> 01:06:20,960 of the key Target for for future 884 01:06:25,849 --> 01:06:23,480 Institute life detection missions 885 01:06:27,829 --> 01:06:25,859 I'm going to talk more about the 886 01:06:29,210 --> 01:06:27,839 Practical side of astrobiology rather 887 01:06:32,329 --> 01:06:29,220 than the theory that we have heard 888 01:06:34,430 --> 01:06:32,339 before maybe we can get together after 889 01:06:36,049 --> 01:06:34,440 it and find some new solutions for the 890 01:06:38,349 --> 01:06:36,059 problems and situations that we've 891 01:06:40,789 --> 01:06:38,359 encountered during our experiments so 892 01:06:42,950 --> 01:06:40,799 there are three levels that we have to 893 01:06:46,910 --> 01:06:42,960 look at when dealing with amino acids 894 01:06:50,569 --> 01:06:46,920 the first is uh kind of a qualitative 895 01:06:54,309 --> 01:06:50,579 problem what type of amino acids can we 896 01:06:57,470 --> 01:06:54,319 detect and what do those tell us 897 01:07:00,470 --> 01:06:57,480 the second is the abundance of these 898 01:07:02,870 --> 01:07:00,480 amino acids so their ratios are they 899 01:07:05,950 --> 01:07:02,880 more similar to what things that we see 900 01:07:08,510 --> 01:07:05,960 here on Earth as the metabolic 901 01:07:10,970 --> 01:07:08,520 processes of microbes or something 902 01:07:14,210 --> 01:07:10,980 completely different and the third is 903 01:07:17,210 --> 01:07:14,220 basically what makes it a lot more 904 01:07:21,049 --> 01:07:17,220 interesting or puts the icing in the 905 01:07:25,130 --> 01:07:21,059 cake is the chirality as you well know 906 01:07:28,670 --> 01:07:25,140 amino acids are basically chiral meaning 907 01:07:30,950 --> 01:07:28,680 that they have uh they are they have two 908 01:07:32,510 --> 01:07:30,960 versions of the same molecule and 909 01:07:34,849 --> 01:07:32,520 they're non-superimposable basically 910 01:07:37,190 --> 01:07:34,859 they're mirror images of each other they 911 01:07:40,730 --> 01:07:37,200 have exactly the same amount of atoms 912 01:07:42,670 --> 01:07:40,740 bonds but they have a totally different 913 01:07:44,870 --> 01:07:42,680 um 914 01:07:45,829 --> 01:07:44,880 structure when we're talking about the 915 01:07:49,730 --> 01:07:45,839 isomers 916 01:07:52,490 --> 01:07:49,740 and getting to know the the ratio of 917 01:07:55,970 --> 01:07:52,500 these amino acids is basically like a 918 01:07:57,410 --> 01:07:55,980 Smoking Gun evidence for life if if you 919 01:07:58,190 --> 01:07:57,420 like 920 01:07:59,809 --> 01:07:58,200 um 921 01:08:03,130 --> 01:07:59,819 but what does it have to do with 922 01:08:06,529 --> 01:08:03,140 radiation well as you all know 923 01:08:07,990 --> 01:08:06,539 as we said here we are experiencing the 924 01:08:12,170 --> 01:08:08,000 effective radiation 925 01:08:14,390 --> 01:08:12,180 but in the early Universe the activity 926 01:08:17,150 --> 01:08:14,400 might have been a lot a lot bigger than 927 01:08:20,510 --> 01:08:17,160 it is today and 928 01:08:22,550 --> 01:08:20,520 there are all sorts of theories that are 929 01:08:24,950 --> 01:08:22,560 some of them are quite established some 930 01:08:27,709 --> 01:08:24,960 of their are some of them are in the 931 01:08:30,950 --> 01:08:27,719 process of proving but the point is that 932 01:08:37,490 --> 01:08:34,370 um sons and stars basically produce 933 01:08:39,410 --> 01:08:37,500 ultraviolet light and if you have this 934 01:08:42,610 --> 01:08:39,420 scattered from the surface basically you 935 01:08:45,829 --> 01:08:42,620 have a polarized light and basically 936 01:08:49,370 --> 01:08:45,839 amino acids and enantiomers which are 937 01:08:51,110 --> 01:08:49,380 which absorb a specific light better 938 01:08:53,570 --> 01:08:51,120 than their counterparts then basically 939 01:08:55,249 --> 01:08:53,580 they get destroyed in the process this 940 01:08:58,070 --> 01:08:55,259 is the same way actually as we detect 941 01:08:59,870 --> 01:08:58,080 the the their ratio but it's also their 942 01:09:01,610 --> 01:08:59,880 Doom if we are talking about high 943 01:09:03,370 --> 01:09:01,620 intensities so this is a pretty much 944 01:09:06,950 --> 01:09:03,380 established model 945 01:09:09,410 --> 01:09:06,960 we can basically replicate these using 946 01:09:12,289 --> 01:09:09,420 all sorts of accelerators and all sorts 947 01:09:16,729 --> 01:09:12,299 of sources to basically mimic this 948 01:09:19,610 --> 01:09:16,739 effect the other one is is a uh um more 949 01:09:21,890 --> 01:09:19,620 of a still about photons but but more of 950 01:09:26,590 --> 01:09:21,900 a having a 951 01:09:30,829 --> 01:09:26,600 um the magnetic effect also 952 01:09:33,590 --> 01:09:30,839 taken into account when dealing with how 953 01:09:36,490 --> 01:09:33,600 radiation affects these molecules and 954 01:09:40,249 --> 01:09:36,500 the third is basically stepping towards 955 01:09:42,890 --> 01:09:40,259 particles and subatomic particles and 956 01:09:44,510 --> 01:09:42,900 how they change the isotopic ratio and 957 01:09:46,970 --> 01:09:44,520 through the isotopic ratio how they 958 01:09:49,269 --> 01:09:46,980 change basically the composition of the 959 01:09:52,849 --> 01:09:49,279 amino acids and having them 960 01:09:55,310 --> 01:09:52,859 change a chirality so these are just the 961 01:09:57,290 --> 01:09:55,320 main theories that we know so far that 962 01:10:00,590 --> 01:09:57,300 work 963 01:10:04,689 --> 01:10:00,600 and in our Laboratories we basically set 964 01:10:07,310 --> 01:10:04,699 out to mimic some of these effects 965 01:10:10,310 --> 01:10:07,320 the accelerator atom queue we have three 966 01:10:13,310 --> 01:10:10,320 of them a small middle one and a big one 967 01:10:17,750 --> 01:10:13,320 they are all considered small in the 968 01:10:20,750 --> 01:10:17,760 field of uh Nuclear Physics but for our 969 01:10:22,430 --> 01:10:20,760 experiments we basically used a tandem 970 01:10:25,149 --> 01:10:22,440 accelerator 971 01:10:29,270 --> 01:10:25,159 which allows 972 01:10:31,430 --> 01:10:29,280 a pretty quick change of ion sources so 973 01:10:34,070 --> 01:10:31,440 basically if you want to irradiate your 974 01:10:36,590 --> 01:10:34,080 sample with hydrogen and then you want 975 01:10:38,689 --> 01:10:36,600 to see how the same scent was affected 976 01:10:41,689 --> 01:10:38,699 by a heavier ion basically you can 977 01:10:43,070 --> 01:10:41,699 change the ions in a matter of hours or 978 01:10:45,229 --> 01:10:43,080 even less if you're if you're 979 01:10:46,790 --> 01:10:45,239 experienced so it has a lot versatility 980 01:10:48,490 --> 01:10:46,800 that's that's the point of having a 981 01:10:52,850 --> 01:10:48,500 tandem accelerator 982 01:10:55,450 --> 01:10:52,860 so on the image you see probably the 983 01:10:58,550 --> 01:10:55,460 closest thing to a real lightsaber 984 01:11:01,810 --> 01:10:58,560 and what you see here on the image in 985 01:11:04,310 --> 01:11:01,820 the top right is basically how uh 986 01:11:07,189 --> 01:11:04,320 hydrogen ions look like when they're 987 01:11:10,209 --> 01:11:07,199 extracted to air from vacuum 988 01:11:14,229 --> 01:11:10,219 and basically 989 01:11:17,990 --> 01:11:14,239 this shows the ionization of the air 990 01:11:19,910 --> 01:11:18,000 that that the accelerated ions are 991 01:11:20,689 --> 01:11:19,920 hitting so 992 01:11:26,689 --> 01:11:20,699 um 993 01:11:29,870 --> 01:11:26,699 and you will connect it later but the 994 01:11:32,390 --> 01:11:29,880 point is that we use the technical 995 01:11:35,209 --> 01:11:32,400 capillary electrophoresis to basically 996 01:11:36,709 --> 01:11:35,219 see what radiation might have to do with 997 01:11:37,870 --> 01:11:36,719 the with the molecules and their 998 01:11:41,209 --> 01:11:37,880 chirality 999 01:11:44,750 --> 01:11:41,219 you see is really a very very friendly 1000 01:11:46,790 --> 01:11:44,760 technique and it's very very simple but 1001 01:11:48,709 --> 01:11:46,800 that's what people use that are 1002 01:11:51,950 --> 01:11:48,719 basically saying who are experts in the 1003 01:11:54,530 --> 01:11:51,960 field but the point is that you have a 1004 01:11:56,990 --> 01:11:54,540 tiny capillary a tiny few silica 1005 01:11:59,689 --> 01:11:57,000 capillary with an inner diameter let's 1006 01:12:01,970 --> 01:11:59,699 say 50 microns and another in another 1007 01:12:04,189 --> 01:12:01,980 diameter of let's say 400 microns and 1008 01:12:05,750 --> 01:12:04,199 when you feel this capillary with an 1009 01:12:07,970 --> 01:12:05,760 electrolyte then you 1010 01:12:10,550 --> 01:12:07,980 and you apply voltage on this system 1011 01:12:12,110 --> 01:12:10,560 basically you will see stuff migrate and 1012 01:12:14,570 --> 01:12:12,120 they will migrate according to their 1013 01:12:16,550 --> 01:12:14,580 hydrodynamic volume to charge ratio in 1014 01:12:18,850 --> 01:12:16,560 this field so what it allows you to do 1015 01:12:21,830 --> 01:12:18,860 it allows you to do to separate 1016 01:12:26,810 --> 01:12:21,840 molecules based on the hydrodynamic 1017 01:12:32,030 --> 01:12:26,820 volume to charge ratio and if you put a 1018 01:12:39,110 --> 01:12:32,040 detector in the 1019 01:12:41,350 --> 01:12:39,120 uh at the specific point of the 1020 01:12:44,870 --> 01:12:41,360 capillary basically 1021 01:12:47,510 --> 01:12:44,880 you can see the molecules migrating 1022 01:12:50,570 --> 01:12:47,520 through the capillary and the specific 1023 01:12:53,649 --> 01:12:50,580 point you get intensity versus time so 1024 01:12:55,790 --> 01:12:53,659 you you see migrating Peaks this 1025 01:12:57,470 --> 01:12:55,800 simulation on the left would like to 1026 01:12:59,510 --> 01:12:57,480 show that but unfortunately it doesn't 1027 01:13:00,649 --> 01:12:59,520 run so you have to believe me that the 1028 01:13:02,209 --> 01:13:00,659 Peaks you're seeing are actually 1029 01:13:03,950 --> 01:13:02,219 migrating through the detector window 1030 01:13:05,649 --> 01:13:03,960 that we're looking at 1031 01:13:08,330 --> 01:13:05,659 and um 1032 01:13:09,350 --> 01:13:08,340 it is using laser induced fluorescence 1033 01:13:11,689 --> 01:13:09,360 well 1034 01:13:14,510 --> 01:13:11,699 uh why are we using laser induced filter 1035 01:13:16,729 --> 01:13:14,520 since the main reason is that to achieve 1036 01:13:19,850 --> 01:13:16,739 High sensitivity it's you can imagine it 1037 01:13:23,030 --> 01:13:19,860 like going or being in a dark room uh 1038 01:13:26,510 --> 01:13:23,040 sleeping and you basically just 1039 01:13:28,010 --> 01:13:26,520 um open up or or open your phone and you 1040 01:13:30,050 --> 01:13:28,020 have a lot of bright light coming in 1041 01:13:31,430 --> 01:13:30,060 even though if you're doing it in the 1042 01:13:34,130 --> 01:13:31,440 broad daylight probably you're not 1043 01:13:36,470 --> 01:13:34,140 affected that much it allows you to 1044 01:13:39,290 --> 01:13:36,480 remove background basically have a great 1045 01:13:41,090 --> 01:13:39,300 big signal and to do that you need some 1046 01:13:43,550 --> 01:13:41,100 molecules that basically have a 1047 01:13:46,090 --> 01:13:43,560 fluorescent property meaning that you're 1048 01:13:48,709 --> 01:13:46,100 excited them over the specific 1049 01:13:52,510 --> 01:13:48,719 wavelength and they respond to you with 1050 01:13:55,370 --> 01:13:52,520 a different wavelength this is a a 1051 01:13:57,169 --> 01:13:55,380 molecule that we used to do the 1052 01:13:59,930 --> 01:13:57,179 conjugation of our amino acids to 1053 01:14:01,090 --> 01:13:59,940 basically enhance the selectivity and 1054 01:14:05,149 --> 01:14:01,100 enhance 1055 01:14:07,729 --> 01:14:05,159 separation efficiency so in order to do 1056 01:14:10,550 --> 01:14:07,739 CE what you have to do is you have to 1057 01:14:15,110 --> 01:14:10,560 have molecules that have a net charge 1058 01:14:17,750 --> 01:14:15,120 other than zero and we have to make them 1059 01:14:21,649 --> 01:14:17,760 visible this molecule here does the two 1060 01:14:24,290 --> 01:14:21,659 things at the same time so basically 1061 01:14:28,729 --> 01:14:24,300 um what what you see here is 1062 01:14:32,530 --> 01:14:28,739 uh the six centimeter from the die 1063 01:14:35,930 --> 01:14:32,540 reacting with the Mi forming a stable 1064 01:14:39,169 --> 01:14:35,940 amide conjugate and this way basically 1065 01:14:41,209 --> 01:14:39,179 you if you if you separate them uh 1066 01:14:44,270 --> 01:14:41,219 you're you're getting a pretty huge 1067 01:14:46,189 --> 01:14:44,280 resolution so what we did is basically 1068 01:14:47,450 --> 01:14:46,199 first developed the buffer system or a 1069 01:14:49,850 --> 01:14:47,460 background detector right the thing that 1070 01:14:52,310 --> 01:14:49,860 you feel the capillary with to do this 1071 01:14:54,350 --> 01:14:52,320 separation it's a pretty simple buffer 1072 01:14:57,410 --> 01:14:54,360 it contains two components and the 1073 01:15:00,649 --> 01:14:57,420 reason behind it was that we had to keep 1074 01:15:02,930 --> 01:15:00,659 in mind the restrictions that a possible 1075 01:15:04,970 --> 01:15:02,940 future Institute life detection Mission 1076 01:15:07,790 --> 01:15:04,980 would have that you're not allowed to 1077 01:15:09,890 --> 01:15:07,800 have a ton of regions you're not allowed 1078 01:15:11,870 --> 01:15:09,900 to have all sorts of mixing to to happen 1079 01:15:13,490 --> 01:15:11,880 you have to make everything simple that 1080 01:15:15,169 --> 01:15:13,500 was the mindset that we had when we were 1081 01:15:17,270 --> 01:15:15,179 doing the experiments and as you see 1082 01:15:20,510 --> 01:15:17,280 we've managed to separate actually 15 1083 01:15:23,330 --> 01:15:20,520 amino acids chirally of the 17 that we 1084 01:15:25,850 --> 01:15:23,340 had in mind 1085 01:15:28,790 --> 01:15:25,860 um why is it a promising technique like 1086 01:15:32,750 --> 01:15:28,800 just like I said suppose a few of moving 1087 01:15:35,689 --> 01:15:32,760 Parts no power consumption easy to 1088 01:15:38,930 --> 01:15:35,699 implement and it's just basically very 1089 01:15:41,570 --> 01:15:38,940 very friendly technique and guys at JP 1090 01:15:43,850 --> 01:15:41,580 are basically are developing this kind 1091 01:15:46,430 --> 01:15:43,860 of technology and what you see here on 1092 01:15:49,370 --> 01:15:46,440 the image is basically the base plate of 1093 01:15:51,290 --> 01:15:49,380 this whole setup is basically the size 1094 01:15:51,830 --> 01:15:51,300 of your laptop 1095 01:15:54,410 --> 01:15:51,840 um 1096 01:15:56,390 --> 01:15:54,420 so uh actually what we did during the 1097 01:15:58,550 --> 01:15:56,400 irradiations well we made some sample 1098 01:16:02,149 --> 01:15:58,560 holders from a drill press to kind of a 1099 01:16:06,189 --> 01:16:02,159 modified drill press and we made 100 1100 01:16:09,410 --> 01:16:06,199 Micron thick pellets of uh racemic 1101 01:16:12,530 --> 01:16:09,420 alanine and we irradiated them here you 1102 01:16:15,229 --> 01:16:12,540 see the simulation how the protein beans 1103 01:16:18,709 --> 01:16:15,239 would actually behave in the 100 Micron 1104 01:16:21,229 --> 01:16:18,719 thick alanine pellet and as you see 1105 01:16:23,570 --> 01:16:21,239 towards the end around 80 microns all 1106 01:16:25,430 --> 01:16:23,580 the ions stop and this is actually where 1107 01:16:28,090 --> 01:16:25,440 the most interesting things happen 1108 01:16:31,250 --> 01:16:28,100 during an iron B analysis or or 1109 01:16:34,310 --> 01:16:31,260 irradiation as well which you see here a 1110 01:16:36,169 --> 01:16:34,320 bit a bit in more detail so we have the 1111 01:16:38,330 --> 01:16:36,179 protons coming in the in the vacuum of 1112 01:16:41,530 --> 01:16:38,340 from the accelerator and then we have a 1113 01:16:44,630 --> 01:16:41,540 window where the protons 1114 01:16:47,270 --> 01:16:44,640 are extracted to the air and then as 1115 01:16:49,550 --> 01:16:47,280 they enter the the amino acids they 1116 01:16:53,870 --> 01:16:49,560 basically lose energy and the nice thing 1117 01:16:56,030 --> 01:16:53,880 about the ions is the that they give off 1118 01:16:58,790 --> 01:16:56,040 all their almost all the energies right 1119 01:17:01,550 --> 01:16:58,800 before they stop and this is actually 1120 01:17:04,370 --> 01:17:01,560 why it's really useful during proton 1121 01:17:07,010 --> 01:17:04,380 therapy and so we irradiated these 1122 01:17:09,110 --> 01:17:07,020 samples with these energies to basically 1123 01:17:11,630 --> 01:17:09,120 and we designed the system to basically 1124 01:17:15,050 --> 01:17:11,640 stop all the ions in the sample and see 1125 01:17:20,870 --> 01:17:15,060 how destruction or any alterations occur 1126 01:17:26,050 --> 01:17:20,880 so moving forward basically you see that 1127 01:17:32,209 --> 01:17:29,689 over D and L I mean erasmic as amino 1128 01:17:34,070 --> 01:17:32,219 acid some of you might see that these 1129 01:17:36,590 --> 01:17:34,080 are not exactly the same height and that 1130 01:17:38,510 --> 01:17:36,600 is the same area this is just the 1131 01:17:40,490 --> 01:17:38,520 control that we were using and we 1132 01:17:43,430 --> 01:17:40,500 compared all our results to these 1133 01:17:46,010 --> 01:17:43,440 control runs so basically with two big 1134 01:17:48,709 --> 01:17:46,020 Peaks and we are happy and if we go 1135 01:17:52,030 --> 01:17:48,719 further we'll be interested more in the 1136 01:17:54,470 --> 01:17:52,040 in the small Peak part of the of the 1137 01:17:56,390 --> 01:17:54,480 electrophilograms as we go with the 1138 01:17:59,630 --> 01:17:56,400 irradiation and as we go with the 1139 01:18:03,350 --> 01:17:59,640 function of those increases so what you 1140 01:18:06,530 --> 01:18:03,360 have here is basically the control that 1141 01:18:08,390 --> 01:18:06,540 I just showed and different doses that 1142 01:18:10,430 --> 01:18:08,400 have reached the sample and it's 1143 01:18:13,910 --> 01:18:10,440 apparent that some of the Peaks are 1144 01:18:16,729 --> 01:18:13,920 clearly increasing some of them show a 1145 01:18:17,570 --> 01:18:16,739 nice correlation 1146 01:18:20,510 --> 01:18:17,580 um 1147 01:18:24,050 --> 01:18:20,520 and some of these Peaks are basically 1148 01:18:27,290 --> 01:18:24,060 coming in duplets and this is what made 1149 01:18:29,950 --> 01:18:27,300 us think that actually although we were 1150 01:18:33,050 --> 01:18:29,960 irradiating wrestling 1151 01:18:36,290 --> 01:18:33,060 alanine we are basically seeing racemic 1152 01:18:39,649 --> 01:18:38,090 um so 1153 01:18:41,990 --> 01:18:39,659 um we're still in the process of 1154 01:18:44,209 --> 01:18:42,000 identifying these molecules 1155 01:18:46,550 --> 01:18:44,219 um and in these radicals that we found 1156 01:18:47,630 --> 01:18:46,560 but they seem to correlate well with the 1157 01:18:49,610 --> 01:18:47,640 dose 1158 01:18:52,010 --> 01:18:49,620 and also another interesting thing 1159 01:18:56,930 --> 01:18:52,020 happened when we were looking at the big 1160 01:18:59,270 --> 01:18:56,940 peaks of the uh amino acids and we were 1161 01:19:01,370 --> 01:18:59,280 just wondering what could this mean what 1162 01:19:04,209 --> 01:19:01,380 you see in the uh in this picture is 1163 01:19:08,930 --> 01:19:04,219 basically as we go with the dose 1164 01:19:11,750 --> 01:19:08,940 the the LD ratio is getting more and 1165 01:19:15,830 --> 01:19:11,760 more hectic which means that we're not 1166 01:19:19,030 --> 01:19:15,840 seeing it going towards one and anterior 1167 01:19:22,550 --> 01:19:19,040 or the other but kind of mixed noisy 1168 01:19:25,270 --> 01:19:22,560 version of the two as we go with those 1169 01:19:27,729 --> 01:19:25,280 higher and higher so in summary 1170 01:19:31,430 --> 01:19:27,739 basically 1171 01:19:34,669 --> 01:19:31,440 we have put together a simple setup and 1172 01:19:36,770 --> 01:19:34,679 measured some radicals that could form 1173 01:19:40,790 --> 01:19:36,780 due to your radiation and we've done it 1174 01:19:42,950 --> 01:19:40,800 in a chiral manner to basically see 1175 01:19:46,850 --> 01:19:42,960 whether our method is capable of 1176 01:19:49,370 --> 01:19:46,860 separating these chiral amino acids and 1177 01:19:52,130 --> 01:19:49,380 more importantly if you think about the 1178 01:19:54,410 --> 01:19:52,140 the next possible or the most possible 1179 01:19:58,310 --> 01:19:54,420 places in our solar system but life 1180 01:20:01,010 --> 01:19:58,320 could be actually there in a in a huge 1181 01:20:02,689 --> 01:20:01,020 radiation environment so I think it's it 1182 01:20:06,169 --> 01:20:02,699 is really necessary to basically create 1183 01:20:08,649 --> 01:20:06,179 a library of radicals simulated here in 1184 01:20:14,450 --> 01:20:08,659 the labs to basically make the work 1185 01:20:16,330 --> 01:20:14,460 easier and the unload this from the 1186 01:20:19,510 --> 01:20:16,340 scientists you will have to basically 1187 01:20:22,070 --> 01:20:19,520 figure out how 1188 01:20:23,570 --> 01:20:22,080 molecules are formed in these high 1189 01:20:25,250 --> 01:20:23,580 radiation environments and what they are 1190 01:20:27,830 --> 01:20:25,260 seeing on the the results when these 1191 01:20:31,790 --> 01:20:27,840 instruments send back the data so 1192 01:20:33,709 --> 01:20:31,800 basically we're trying to to establish a 1193 01:20:36,110 --> 01:20:33,719 big Library where all sorts of amino 1194 01:20:39,229 --> 01:20:36,120 acids mixers and single ones are 1195 01:20:42,310 --> 01:20:39,239 irradiated or with all sorts of 1196 01:20:45,950 --> 01:20:42,320 radiation sources and see 1197 01:20:48,050 --> 01:20:45,960 what products are there and what can be 1198 01:20:49,310 --> 01:20:48,060 identified using this technology so I'd 1199 01:20:49,670 --> 01:20:49,320 like to thank you very much for your 1200 01:20:54,410 --> 01:20:49,680 attention 1201 01:20:59,630 --> 01:20:57,350 foreign 1202 01:21:02,570 --> 01:20:59,640 okay we have time for two questions for 1203 01:21:04,790 --> 01:21:02,580 mate Chad 1204 01:21:07,669 --> 01:21:04,800 hi uh Chad pazoriski from Georgia Tech 1205 01:21:10,250 --> 01:21:07,679 uh I was really glad to see celif 1206 01:21:12,950 --> 01:21:10,260 because it's a method that I work with 1207 01:21:15,110 --> 01:21:12,960 as well and so uh seeing it being used 1208 01:21:16,669 --> 01:21:15,120 around is is wonderful and I have a 1209 01:21:21,050 --> 01:21:16,679 question about your chiral method which 1210 01:21:23,330 --> 01:21:21,060 seemed to work very well um so uh did 1211 01:21:25,130 --> 01:21:23,340 you develop this in its entirety or uh 1212 01:21:27,530 --> 01:21:25,140 when did you develop it where basically 1213 01:21:30,410 --> 01:21:27,540 I wanted all about the Cairo method is 1214 01:21:32,630 --> 01:21:30,420 it published and uh yeah it's not 1215 01:21:35,050 --> 01:21:32,640 published yet but we've developed it in 1216 01:21:39,590 --> 01:21:35,060 collaboration with JPL 1217 01:21:41,689 --> 01:21:39,600 basically the key thing here is that to 1218 01:21:44,090 --> 01:21:41,699 do chiro separation the way you can 1219 01:21:47,270 --> 01:21:44,100 imagine is is that when you have these 1220 01:21:49,189 --> 01:21:47,280 molecules in a solution and that they 1221 01:21:51,110 --> 01:21:49,199 migrate through the capillary if you 1222 01:21:54,410 --> 01:21:51,120 have some additional additives in your 1223 01:21:55,030 --> 01:21:54,420 buffer basically you can in 1224 01:21:58,310 --> 01:21:55,040 um 1225 01:22:00,130 --> 01:21:58,320 emphasize or or basically manipulate how 1226 01:22:04,729 --> 01:22:00,140 these 1227 01:22:05,709 --> 01:22:04,739 molecules behave but I mean that if you 1228 01:22:08,770 --> 01:22:05,719 have 1229 01:22:12,370 --> 01:22:08,780 sugars like cycle Jack strains these are 1230 01:22:15,410 --> 01:22:12,380 circular long oligomers 1231 01:22:19,070 --> 01:22:15,420 basically these amino acids are as they 1232 01:22:21,410 --> 01:22:19,080 migrate they meet with these cavities 1233 01:22:23,390 --> 01:22:21,420 and they basically form an inclusion 1234 01:22:25,310 --> 01:22:23,400 complex they go in they go out they go 1235 01:22:28,370 --> 01:22:25,320 in they go out and some of the Indian 1236 01:22:30,229 --> 01:22:28,380 tumors are staying longer in this cavity 1237 01:22:32,090 --> 01:22:30,239 and some of them are staying for a short 1238 01:22:33,950 --> 01:22:32,100 period of time and as they migrate they 1239 01:22:37,189 --> 01:22:33,960 basically separate and this is what we 1240 01:22:39,890 --> 01:22:37,199 see and in this context to basically 1241 01:22:42,050 --> 01:22:39,900 answer your question we had a lot of 1242 01:22:44,990 --> 01:22:42,060 constraints first of all we are not 1243 01:22:47,990 --> 01:22:45,000 allowed to have a ton of additives a ton 1244 01:22:49,610 --> 01:22:48,000 of stuff in the buffer because an 1245 01:22:52,490 --> 01:22:49,620 instrument has to be able to do this on 1246 01:22:55,729 --> 01:22:52,500 its own its own so we had two components 1247 01:22:57,050 --> 01:22:55,739 in it which is the habish or hippies I 1248 01:23:00,830 --> 01:22:57,060 don't know how they say it in English 1249 01:23:03,410 --> 01:23:00,840 properly AGP yes and and the other one 1250 01:23:06,610 --> 01:23:03,420 is the md40 which is basically similar 1251 01:23:10,669 --> 01:23:06,620 to cycle dextrins but it consists of 1252 01:23:14,090 --> 01:23:10,679 sugar oligomers or actually monomers and 1253 01:23:16,610 --> 01:23:14,100 as you go you have at the end at the 1254 01:23:19,490 --> 01:23:16,620 beginning one sugar one glucose unit and 1255 01:23:21,470 --> 01:23:19,500 as you go two three four Etc and these 1256 01:23:24,709 --> 01:23:21,480 after some around seven they start to 1257 01:23:27,410 --> 01:23:24,719 become helico and you have a long long 1258 01:23:30,770 --> 01:23:27,420 longer chains of these sugars and 1259 01:23:36,649 --> 01:23:30,780 basically it enhanced the effectiveness 1260 01:23:36,659 --> 01:23:44,750 last question 1261 01:23:48,470 --> 01:23:46,550 hi my name is shiv agrawal from Western 1262 01:23:49,910 --> 01:23:48,480 Michigan University so you have used 1263 01:23:52,330 --> 01:23:49,920 protons for irradiation have you 1264 01:23:55,310 --> 01:23:52,340 considered using leptons 1265 01:23:57,709 --> 01:23:55,320 we know it should be done and it should 1266 01:24:00,229 --> 01:23:57,719 be interesting but we wanted to do to 1267 01:24:03,649 --> 01:24:00,239 use the facility that we have available 1268 01:24:06,010 --> 01:24:03,659 and currently we are only are only able 1269 01:24:09,350 --> 01:24:06,020 only able to do 1270 01:24:11,630 --> 01:24:09,360 protons and heavy ions 1271 01:24:14,209 --> 01:24:11,640 it would be a nice thing to move forward 1272 01:24:16,130 --> 01:24:14,219 and do all sorts of experiments on this 1273 01:24:17,270 --> 01:24:16,140 on this field as well I'm happy to 1274 01:24:19,430 --> 01:24:17,280 collaborate 1275 01:24:21,470 --> 01:24:19,440 second thing is have you used variable 1276 01:24:23,450 --> 01:24:21,480 energies for protons at what energies 1277 01:24:25,850 --> 01:24:23,460 are you we in this experiment we used 1278 01:24:28,130 --> 01:24:25,860 only one energy we didn't want to have 1279 01:24:30,649 --> 01:24:28,140 too many variables if it's hard enough 1280 01:24:33,530 --> 01:24:30,659 to figure out whether with 100 Micron 1281 01:24:36,470 --> 01:24:33,540 thickness of a palette are we able to to 1282 01:24:38,810 --> 01:24:36,480 robustly uh do experiments and 1283 01:24:40,970 --> 01:24:38,820 unfortunately uh with a simple system 1284 01:24:44,030 --> 01:24:40,980 and with a great care we were able to 1285 01:24:45,709 --> 01:24:44,040 basically make it uh work so this was 1286 01:24:49,430 --> 01:24:45,719 the first goal that we wanted to achieve 1287 01:24:52,130 --> 01:24:49,440 and and uh of course we have all sorts 1288 01:24:55,550 --> 01:24:52,140 of experiments either already running or 1289 01:24:58,130 --> 01:24:55,560 in plan to vary energies where I 1290 01:25:00,290 --> 01:24:58,140 actually the the dose rate which is 1291 01:25:03,910 --> 01:25:00,300 actually a much more important thing it 1292 01:25:07,250 --> 01:25:03,920 looks like it is a key factor in some 1293 01:25:09,770 --> 01:25:07,260 instances and also doing everything in 1294 01:25:11,450 --> 01:25:09,780 vacuum doing everything it was in air 1295 01:25:13,250 --> 01:25:11,460 but we also would like to do it in 1296 01:25:14,090 --> 01:25:13,260 vacuum and also in cold temperatures as 1297 01:25:15,950 --> 01:25:14,100 well 1298 01:25:17,450 --> 01:25:15,960 thanks a lot 1299 01:25:18,160 --> 01:25:17,460 all right thank you very much mate 1300 01:25:26,390 --> 01:25:18,170 thanks very much 1301 01:25:28,430 --> 01:25:26,400 [Applause] 1302 01:25:32,330 --> 01:25:28,440 okay and for our next speaker we have 1303 01:25:45,330 --> 01:25:32,340 young Hua Kang from pohang University 1304 01:26:06,709 --> 01:26:02,780 [Music] 1305 01:26:18,280 --> 01:26:08,260 thank you 1306 01:26:43,189 --> 01:26:33,090 [Music] 1307 01:26:43,199 --> 01:26:48,590 foreign 1308 01:27:18,649 --> 01:27:03,410 [Music] 1309 01:27:18,659 --> 01:27:22,480 foreign 1310 01:28:28,189 --> 01:27:33,730 [Music] 1311 01:28:28,199 --> 01:28:34,360 thank you 1312 01:29:04,729 --> 01:28:39,810 [Music] 1313 01:29:17,530 --> 01:29:08,570 foreign 1314 01:29:40,430 --> 01:29:35,010 [Music] 1315 01:29:59,750 --> 01:29:40,440 foreign 1316 01:30:20,760 --> 01:30:12,320 [Music] 1317 01:31:03,729 --> 01:30:20,770 foreign 1318 01:31:29,930 --> 01:31:03,739 [Music] 1319 01:31:37,629 --> 01:31:29,940 foreign 1320 01:32:00,410 --> 01:31:37,639 [Music] 1321 01:32:30,010 --> 01:32:02,320 foreign 1322 01:32:39,210 --> 01:32:37,430 [Music] 1323 01:32:47,310 --> 01:32:39,220 foreign 1324 01:32:47,320 --> 01:33:10,910 [Music] 1325 01:33:10,920 --> 01:33:14,480 thank you 1326 01:33:48,830 --> 01:33:46,669 [Music] 1327 01:33:50,660 --> 01:33:48,840 feet 1328 01:33:58,160 --> 01:33:50,670 s 1329 01:34:19,560 --> 01:33:58,170 foreign 1330 01:34:19,570 --> 01:34:35,270 [Music] 1331 01:34:35,280 --> 01:34:39,240 foreign 1332 01:35:12,170 --> 01:35:10,430 [Music] 1333 01:35:37,370 --> 01:35:12,180 foreign 1334 01:36:07,370 --> 01:35:37,380 [Music] 1335 01:36:07,380 --> 01:36:11,530 foreign 1336 01:36:11,540 --> 01:36:26,030 [Music] 1337 01:36:53,240 --> 01:36:27,860 foreign 1338 01:37:42,200 --> 01:37:13,510 [Music] 1339 01:37:53,090 --> 01:37:42,210 foreign 1340 01:38:07,490 --> 01:37:59,720 [Music] 1341 01:38:42,370 --> 01:38:09,190 foreign 1342 01:38:44,570 --> 01:38:42,380 [Music] 1343 01:38:57,720 --> 01:38:44,580 thank you 1344 01:39:11,560 --> 01:39:10,090 [Music] 1345 01:39:26,120 --> 01:39:11,570 thank you 1346 01:39:34,580 --> 01:39:33,310 [Music] 1347 01:39:55,910 --> 01:39:34,590 thank you 1348 01:39:58,030 --> 01:39:55,920 [Music] 1349 01:40:17,080 --> 01:39:58,040 foreign 1350 01:40:46,490 --> 01:40:35,400 [Music] 1351 01:40:48,350 --> 01:40:46,500 break for about half an hour so feel 1352 01:40:50,930 --> 01:40:48,360 free to go to Surfside get coffee tea 1353 01:40:52,610 --> 01:40:50,940 snacks whatever you need we also have 1354 01:40:54,110 --> 01:40:52,620 that courtyard space you can hang out 1355 01:40:56,750 --> 01:40:54,120 out here in the lawn there's also 1356 01:40:59,149 --> 01:40:56,760 another lawn over there but yeah we'll 1357 01:41:01,250 --> 01:40:59,159 meet back at 10 30. 1358 01:41:03,470 --> 01:41:01,260 oh and also outside there's all those 1359 01:41:15,530 --> 01:41:03,480 coolers those are just full of Seltzer's 1360 01:41:19,860 --> 01:41:18,370 [Music] 1361 01:41:34,070 --> 01:41:19,870 thank you 1362 01:41:34,080 --> 01:41:36,360 foreign 1363 01:42:39,410 --> 01:42:00,570 [Music] 1364 01:42:41,629 --> 01:42:39,420 foreign 1365 01:42:44,040 --> 01:42:41,639 [Music] 1366 01:42:57,450 --> 01:42:44,050 foreign 1367 01:43:48,940 --> 01:43:17,480 [Music] 1368 01:43:56,030 --> 01:43:48,950 foreign 1369 01:43:58,640 --> 01:43:56,040 [Music] 1370 01:44:35,770 --> 01:43:58,650 foreign 1371 01:45:10,669 --> 01:45:00,380 [Music] 1372 01:45:39,020 --> 01:45:12,930 foreign 1373 01:46:25,310 --> 01:45:45,210 [Music] 1374 01:47:23,520 --> 01:46:27,380 foreign 1375 01:47:42,210 --> 01:47:39,709 [Music] 1376 01:48:19,470 --> 01:47:42,220 foreign 1377 01:48:48,109 --> 01:48:38,149 [Music] 1378 01:48:59,750 --> 01:48:50,570 detailing 1379 01:48:59,760 --> 01:49:37,910 [Music] 1380 01:49:43,130 --> 01:49:40,609 you're unusually by this time it's like 1381 01:49:49,870 --> 01:49:43,140 totally 1382 01:50:08,990 --> 01:49:52,250 [Music] 1383 01:50:23,700 --> 01:50:11,400 something 1384 01:50:34,070 --> 01:50:30,890 [Music] 1385 01:50:36,590 --> 01:50:34,080 okay yeah so I already have 1386 01:50:39,150 --> 01:50:36,600 um I only have 1387 01:50:54,770 --> 01:50:39,160 two days 1388 01:50:55,590 --> 01:50:54,780 [Music] 1389 01:51:03,960 --> 01:50:55,600 oh yeah 1390 01:51:23,380 --> 01:51:12,820 [Music] 1391 01:52:28,420 --> 01:51:23,390 foreign 1392 01:52:34,540 --> 01:52:32,990 [Music] 1393 01:53:09,050 --> 01:52:34,550 thank you 1394 01:53:38,500 --> 01:53:36,370 [Music] 1395 01:53:46,430 --> 01:53:38,510 thank you 1396 01:54:50,910 --> 01:53:46,440 [Music] 1397 01:54:58,010 --> 01:54:50,920 foreign 1398 01:54:59,920 --> 01:54:58,020 [Music] 1399 01:55:18,870 --> 01:54:59,930 foreign 1400 01:57:05,050 --> 01:55:24,860 [Music] 1401 01:57:05,060 --> 01:57:08,790 thank you 1402 01:57:37,790 --> 01:57:35,470 [Music] 1403 01:57:42,190 --> 01:57:37,800 thank you 1404 01:58:10,310 --> 01:57:59,270 [Music] 1405 01:58:22,720 --> 01:58:11,320 thank you 1406 01:58:48,530 --> 01:58:40,170 [Music] 1407 01:58:48,540 --> 01:58:55,600 foreign 1408 02:00:09,830 --> 01:59:18,950 [Music] 1409 02:00:09,840 --> 02:00:12,580 foreign 1410 02:00:42,850 --> 02:00:30,880 [Music] 1411 02:00:57,910 --> 02:00:42,860 let's see 1412 02:00:57,920 --> 02:01:01,170 thank you 1413 02:01:12,740 --> 02:01:10,010 [Music] 1414 02:01:31,140 --> 02:01:12,750 foreign 1415 02:01:50,450 --> 02:01:44,720 [Music] 1416 02:01:50,460 --> 02:01:53,630 foreign 1417 02:02:43,980 --> 02:02:01,880 [Music] 1418 02:03:04,950 --> 02:02:43,990 foreign 1419 02:03:09,780 --> 02:03:07,490 [Music] 1420 02:03:32,750 --> 02:03:09,790 foreign 1421 02:03:58,910 --> 02:03:39,830 [Music] 1422 02:03:58,920 --> 02:04:03,140 foreign 1423 02:04:03,150 --> 02:04:38,510 [Music] 1424 02:04:59,380 --> 02:04:40,790 foreign 1425 02:05:15,250 --> 02:05:09,240 [Music] 1426 02:05:15,260 --> 02:05:21,340 thank you 1427 02:05:21,350 --> 02:05:25,810 [Music] 1428 02:05:25,820 --> 02:05:37,290 thank you 1429 02:05:45,890 --> 02:05:44,089 [Music] 1430 02:05:54,500 --> 02:05:45,900 foreign 1431 02:06:14,570 --> 02:06:09,240 [Music] 1432 02:06:46,390 --> 02:06:15,900 foreign 1433 02:07:05,100 --> 02:06:47,870 thank you 1434 02:07:13,850 --> 02:07:07,370 [Music] 1435 02:07:13,860 --> 02:07:27,090 foreign 1436 02:07:46,870 --> 02:07:40,290 [Music] 1437 02:07:50,290 --> 02:07:48,510 thank you 1438 02:07:52,250 --> 02:07:50,300 [Music] 1439 02:07:54,470 --> 02:07:52,260 all right everybody we're going to start 1440 02:07:56,990 --> 02:07:54,480 the next talk session life on the edge 1441 02:08:03,649 --> 02:07:57,000 and our first presenter is Lauren Lowe 1442 02:08:08,810 --> 02:08:06,350 hi everyone so I'm Lauren and I'm from 1443 02:08:10,370 --> 02:08:08,820 Anna Lang's Lab at unsw Sydney in 1444 02:08:12,530 --> 02:08:10,380 Australia and today I'm going to tell 1445 02:08:17,089 --> 02:08:12,540 you a bit about the work I do on model 1446 02:08:20,930 --> 02:08:19,010 so I'm sure many of us here are trying 1447 02:08:23,689 --> 02:08:20,940 to answer the question of how did life 1448 02:08:26,390 --> 02:08:23,699 on earth begin now I'm focusing on a 1449 02:08:28,790 --> 02:08:26,400 very very specific point in time when 1450 02:08:30,950 --> 02:08:28,800 life had maybe begun to transition from 1451 02:08:32,810 --> 02:08:30,960 super simple primitive cells perhaps 1452 02:08:35,030 --> 02:08:32,820 composed of a fatty acid bilayer 1453 02:08:36,950 --> 02:08:35,040 membrane it's a more complex protocells 1454 02:08:39,410 --> 02:08:36,960 or primitive cells more akin to Modern 1455 02:08:41,270 --> 02:08:39,420 Biology at this point in time we'd 1456 02:08:43,729 --> 02:08:41,280 started to see the emergence of 1457 02:08:46,970 --> 02:08:43,739 phospholipids and some simple enzymes 1458 02:08:48,950 --> 02:08:46,980 but we hadn't yet thanks but we hadn't 1459 02:08:51,109 --> 02:08:48,960 yet seen the emergence of all the 1460 02:08:53,330 --> 02:08:51,119 complex cellular cellular Machinery that 1461 02:08:55,129 --> 02:08:53,340 exists in our cells so things like 1462 02:08:56,870 --> 02:08:55,139 membrane transport mechanisms for 1463 02:08:58,609 --> 02:08:56,880 example that transport nutrients and 1464 02:09:01,310 --> 02:08:58,619 waste molecules out of the cell maybe 1465 02:09:03,470 --> 02:09:01,320 they hadn't come around yet so that begs 1466 02:09:05,089 --> 02:09:03,480 the question how are these protocells 1467 02:09:06,709 --> 02:09:05,099 actually able to feed themselves how 1468 02:09:08,209 --> 02:09:06,719 were they able to grow how are they able 1469 02:09:11,149 --> 02:09:08,219 to divide 1470 02:09:13,070 --> 02:09:11,159 so I'm trying to answer this question by 1471 02:09:15,229 --> 02:09:13,080 building a propagating synthetic cell 1472 02:09:16,970 --> 02:09:15,239 what that basically means is it's an 1473 02:09:19,129 --> 02:09:16,980 artificial cell that is able to feed 1474 02:09:20,450 --> 02:09:19,139 itself can grow it can divide and I'm 1475 02:09:22,370 --> 02:09:20,460 trying to achieve this using the 1476 02:09:24,709 --> 02:09:22,380 simplest components possible to try and 1477 02:09:26,810 --> 02:09:24,719 understand how life transitioned into 1478 02:09:28,430 --> 02:09:26,820 what we know it as today 1479 02:09:31,490 --> 02:09:28,440 so this involves a pretty large 1480 02:09:33,950 --> 02:09:31,500 collaboration and with my collaborator 1481 02:09:36,589 --> 02:09:33,960 in Japan yutatsu he's been able to build 1482 02:09:39,290 --> 02:09:36,599 a preliminary synthetic cell composed of 1483 02:09:42,229 --> 02:09:39,300 a phospholipid bilayer membrane also 1484 02:09:44,990 --> 02:09:42,239 known as a vesicle and this vesicle is 1485 02:09:47,629 --> 02:09:45,000 composed of a mixture of popc and popg 1486 02:09:49,790 --> 02:09:47,639 two types of phospholipids and within 1487 02:09:51,950 --> 02:09:49,800 this vesicle we have a system that can 1488 02:09:54,669 --> 02:09:51,960 be used to actually synthesize fatty 1489 02:09:56,450 --> 02:09:54,679 acids and eventually synthesize 1490 02:09:58,550 --> 02:09:56,460 phospholipids that can then be 1491 02:10:00,770 --> 02:09:58,560 incorporated into the bilayer membrane 1492 02:10:02,750 --> 02:10:00,780 actually allowing it to grow 1493 02:10:05,629 --> 02:10:02,760 now one of the big problems with this 1494 02:10:07,490 --> 02:10:05,639 system is that you can only encapsulate 1495 02:10:09,169 --> 02:10:07,500 a small number of nutrients actually 1496 02:10:11,089 --> 02:10:09,179 within the synthetic cell within the 1497 02:10:13,490 --> 02:10:11,099 vesicle there's only room for so many 1498 02:10:15,530 --> 02:10:13,500 molecules and if you encapsulate as many 1499 02:10:17,390 --> 02:10:15,540 as you can you only really get one to 1500 02:10:19,370 --> 02:10:17,400 two percent membrane growth which isn't 1501 02:10:21,109 --> 02:10:19,380 really sustainable for a cell that we 1502 02:10:23,810 --> 02:10:21,119 want to make grow and divide 1503 02:10:26,089 --> 02:10:23,820 so what we really need is some sort of 1504 02:10:28,609 --> 02:10:26,099 regular nutrient Supply so we need an 1505 02:10:31,070 --> 02:10:28,619 external feedstock of nutrients that can 1506 02:10:32,570 --> 02:10:31,080 actually permeate the lipid bilayer 1507 02:10:34,550 --> 02:10:32,580 membrane so make its way from the 1508 02:10:36,189 --> 02:10:34,560 outside of the cell into to the inside 1509 02:10:39,649 --> 02:10:36,199 of the cell that way we can actually 1510 02:10:41,510 --> 02:10:39,659 achieve continual membrane growth 1511 02:10:43,010 --> 02:10:41,520 so that's my role in this project I'm 1512 02:10:44,450 --> 02:10:43,020 trying to figure out a way that we can 1513 02:10:46,609 --> 02:10:44,460 actually get the nutrients that we need 1514 02:10:48,470 --> 02:10:46,619 for the synthetic cell to function to 1515 02:10:50,089 --> 02:10:48,480 make its way across the lipid bilayer 1516 02:10:51,950 --> 02:10:50,099 membranes the interior of the synthetic 1517 02:10:53,810 --> 02:10:51,960 cell 1518 02:10:55,370 --> 02:10:53,820 so in order to do that I've needed a 1519 02:10:57,830 --> 02:10:55,380 technique that can be used to monitor 1520 02:10:59,810 --> 02:10:57,840 solute permeability or the permeability 1521 02:11:01,609 --> 02:10:59,820 of different nutrients and to do that 1522 02:11:04,010 --> 02:11:01,619 I'm using what's known as a shrink soil 1523 02:11:06,290 --> 02:11:04,020 assay basically that involves preparing 1524 02:11:08,149 --> 02:11:06,300 vesicles encapsulating a fluorescent dye 1525 02:11:10,310 --> 02:11:08,159 known as calcine 1526 02:11:13,070 --> 02:11:10,320 when you mix these vesicles with your 1527 02:11:15,169 --> 02:11:13,080 solute or your nutrient interests the 1528 02:11:17,410 --> 02:11:15,179 difference in osmolarity actually causes 1529 02:11:20,030 --> 02:11:17,420 the vesicles to shrink because water 1530 02:11:21,890 --> 02:11:20,040 rapidly exits the vesicle and we kind of 1531 02:11:23,689 --> 02:11:21,900 see this these shriveled up sort of 1532 02:11:25,910 --> 02:11:23,699 shrunken structures 1533 02:11:27,530 --> 02:11:25,920 and because we've had water exit the 1534 02:11:29,750 --> 02:11:27,540 vesicles we've actually had an increase 1535 02:11:31,609 --> 02:11:29,760 in concentration of the diet that's on 1536 02:11:33,229 --> 02:11:31,619 the inside of these vesicles and that 1537 02:11:35,810 --> 02:11:33,239 actually causes the fluorescent signal 1538 02:11:37,010 --> 02:11:35,820 to decrease because calcium is a 1539 02:11:39,470 --> 02:11:37,020 self-quenching diet above certain 1540 02:11:41,390 --> 02:11:39,480 concentrations so at high concentrations 1541 02:11:42,890 --> 02:11:41,400 the fluorescence actually goes down 1542 02:11:44,689 --> 02:11:42,900 rather than going up so it's a little 1543 02:11:48,530 --> 02:11:44,699 bit counter-intuitive 1544 02:11:50,149 --> 02:11:48,540 but over time if we have a permeable 1545 02:11:52,129 --> 02:11:50,159 solute so a solute that does actually 1546 02:11:54,109 --> 02:11:52,139 enter the vesicle you'll start to see 1547 02:11:55,490 --> 02:11:54,119 the vesicles slowly swell up again and 1548 02:11:58,010 --> 02:11:55,500 it'll roughly get back to its original 1549 02:11:59,810 --> 02:11:58,020 size and with that we have a decrease in 1550 02:12:01,370 --> 02:11:59,820 calcium concentration so we have an 1551 02:12:03,470 --> 02:12:01,380 increase in the fluorescence roughly to 1552 02:12:05,390 --> 02:12:03,480 what it was to begin with 1553 02:12:07,669 --> 02:12:05,400 and we can basically monitor that whole 1554 02:12:08,689 --> 02:12:07,679 process using some sort of fluorimeter 1555 02:12:10,430 --> 02:12:08,699 or something that can measure 1556 02:12:12,649 --> 02:12:10,440 fluorescence and we can monitor the 1557 02:12:13,970 --> 02:12:12,659 changes intensity over the time so we 1558 02:12:15,770 --> 02:12:13,980 can see initially the intensity is 1559 02:12:17,209 --> 02:12:15,780 somewhere up here and then with the 1560 02:12:19,550 --> 02:12:17,219 addition of the solute the intensity 1561 02:12:21,530 --> 02:12:19,560 drops down and then if we have a 1562 02:12:23,570 --> 02:12:21,540 permeable solute that signal will start 1563 02:12:26,030 --> 02:12:23,580 to recover and restart to see the 1564 02:12:27,890 --> 02:12:26,040 original intensity kind of values there 1565 02:12:29,629 --> 02:12:27,900 now because these intensities are kind 1566 02:12:31,669 --> 02:12:29,639 of a direct measure of the calcium 1567 02:12:33,830 --> 02:12:31,679 concentration we can convert 1568 02:12:36,169 --> 02:12:33,840 concentration to volume so the plots 1569 02:12:39,229 --> 02:12:36,179 I'll be showing you today show the 1570 02:12:40,910 --> 02:12:39,239 changes in volume over time 1571 02:12:42,709 --> 02:12:40,920 and it's just worth noting that the 1572 02:12:44,750 --> 02:12:42,719 initial stage where the vesicles shrink 1573 02:12:46,550 --> 02:12:44,760 and swivel up shrivel up actually 1574 02:12:48,350 --> 02:12:46,560 happens very quickly and the 1575 02:12:49,490 --> 02:12:48,360 experimental setup I currently have I 1576 02:12:51,530 --> 02:12:49,500 can't actually see that because it just 1577 02:12:53,390 --> 02:12:51,540 happens too fast so the data I'll be 1578 02:12:55,729 --> 02:12:53,400 showing you is just the recovery of that 1579 02:12:59,270 --> 02:12:57,589 so the basic workflow for a lot of my 1580 02:13:01,250 --> 02:12:59,280 experiments is to First prepare the 1581 02:13:04,550 --> 02:13:01,260 vesicles composed of an eagle mixture of 1582 02:13:06,890 --> 02:13:04,560 popc popg in 50 millimolar happy so 1583 02:13:09,709 --> 02:13:06,900 that's just the buffer it's roughly 1584 02:13:11,209 --> 02:13:09,719 buffering around physiological pH and 1585 02:13:12,709 --> 02:13:11,219 these bicycles are all encap all 1586 02:13:15,290 --> 02:13:12,719 encapsulate that fluorescent diode 1587 02:13:17,629 --> 02:13:15,300 calcium and then make sure all the 1588 02:13:19,729 --> 02:13:17,639 unencapsulated calcium is removed and I 1589 02:13:21,770 --> 02:13:19,739 mix the vesicles with the solute all the 1590 02:13:24,169 --> 02:13:21,780 nutrient of interest and monitor the 1591 02:13:25,490 --> 02:13:24,179 changes in fluorescence over time and 1592 02:13:28,250 --> 02:13:25,500 then determine the changes in volume 1593 02:13:31,790 --> 02:13:30,109 so this is what some of the data looks 1594 02:13:34,790 --> 02:13:31,800 like on the left we can see some 1595 02:13:36,770 --> 02:13:34,800 examples of some permeable solutes so 1596 02:13:39,410 --> 02:13:36,780 our control here was the 50 millimolar 1597 02:13:41,149 --> 02:13:39,420 happyes in the blue and all of this data 1598 02:13:43,609 --> 02:13:41,159 is normalized to the volume of that 1599 02:13:45,649 --> 02:13:43,619 control at time zero so we see in the 1600 02:13:47,450 --> 02:13:45,659 blue 50mm Heavies it's just a flat line 1601 02:13:49,250 --> 02:13:47,460 there not much is changing and that's 1602 02:13:50,990 --> 02:13:49,260 what we'd expect it's our control it's 1603 02:13:53,510 --> 02:13:51,000 what we made our vesicles in so we don't 1604 02:13:55,069 --> 02:13:53,520 expect any volume change there but when 1605 02:13:58,189 --> 02:13:55,079 we mix our vesicles with something like 1606 02:14:00,350 --> 02:13:58,199 glucose or glycine for example so the 1607 02:14:02,390 --> 02:14:00,360 red and the purple we see that 1608 02:14:04,189 --> 02:14:02,400 characteristic curve telling us that the 1609 02:14:06,169 --> 02:14:04,199 volume is actually increasing after the 1610 02:14:08,089 --> 02:14:06,179 vesicles initially kind of shriveled up 1611 02:14:09,890 --> 02:14:08,099 so that tells us that these two solutes 1612 02:14:12,109 --> 02:14:09,900 are both permeable across these lipid 1613 02:14:14,089 --> 02:14:12,119 bilayer membranes and glycine is 1614 02:14:16,970 --> 02:14:14,099 actually more permeable than the glucose 1615 02:14:19,970 --> 02:14:16,980 because it increases at a faster rate 1616 02:14:20,990 --> 02:14:19,980 on that plot I also have glycerol at 1617 02:14:23,209 --> 02:14:21,000 first glance it kind of looks like 1618 02:14:25,189 --> 02:14:23,219 nothing happens there but glycerol is 1619 02:14:27,169 --> 02:14:25,199 known to be super permeable across lipid 1620 02:14:29,149 --> 02:14:27,179 bilayers so it's likely that I just 1621 02:14:31,010 --> 02:14:29,159 actually missed that initial shrinkage 1622 02:14:32,390 --> 02:14:31,020 and swelling stage so it just looks like 1623 02:14:33,649 --> 02:14:32,400 nothing's happened right now because I 1624 02:14:35,330 --> 02:14:33,659 missed the first kind of couple minutes 1625 02:14:37,430 --> 02:14:35,340 of this process 1626 02:14:39,589 --> 02:14:37,440 now on the other plot we have some 1627 02:14:41,510 --> 02:14:39,599 examples of some impermeable sites and 1628 02:14:42,950 --> 02:14:41,520 you can see there's quite a few there so 1629 02:14:45,050 --> 02:14:42,960 a lot of the solutes I've looked at so 1630 02:14:46,790 --> 02:14:45,060 far are quite impermeable and that's we 1631 02:14:48,470 --> 02:14:46,800 can see that there's like those flat 1632 02:14:50,510 --> 02:14:48,480 lines at the bottom there there's no 1633 02:14:52,189 --> 02:14:50,520 increase in volume over time so over 1634 02:14:54,350 --> 02:14:52,199 these this time frame none of these 1635 02:14:56,089 --> 02:14:54,360 solutes are permeable which is kind of 1636 02:14:57,890 --> 02:14:56,099 disappointing because a lot of these 1637 02:15:01,310 --> 02:14:57,900 solutes would be useful nutrients for a 1638 02:15:03,050 --> 02:15:01,320 synthetic cell things like amp ATP for 1639 02:15:05,450 --> 02:15:03,060 energy and then something like sodium 1640 02:15:07,250 --> 02:15:05,460 acetate I was hoping to use as a carbon 1641 02:15:10,310 --> 02:15:07,260 source to actually synthesize fatty 1642 02:15:12,290 --> 02:15:10,320 acids and then the phospholipids 1643 02:15:13,729 --> 02:15:12,300 but it's not particularly surprising 1644 02:15:15,830 --> 02:15:13,739 that a lot of these solutes were 1645 02:15:17,270 --> 02:15:15,840 impermeable It's relatively well 1646 02:15:19,310 --> 02:15:17,280 established in literature child that 1647 02:15:21,109 --> 02:15:19,320 phospholipid bilayers aren't the most 1648 02:15:23,330 --> 02:15:21,119 permeable things especially when 1649 02:15:25,669 --> 02:15:23,340 comparing them to a fatty acid bilaya 1650 02:15:26,930 --> 02:15:25,679 for example so fatty acid bilayers are 1651 02:15:29,450 --> 02:15:26,940 kind of useful to think about because 1652 02:15:31,609 --> 02:15:29,460 they have been proposed to have made up 1653 02:15:33,950 --> 02:15:31,619 the first protocell membranes before we 1654 02:15:35,750 --> 02:15:33,960 saw the emergence of phospholipids and 1655 02:15:38,330 --> 02:15:35,760 we can see in this plot here for 1656 02:15:40,790 --> 02:15:38,340 something like glucose it's a bit less 1657 02:15:42,290 --> 02:15:40,800 permeable in phospholipids than in fatty 1658 02:15:44,450 --> 02:15:42,300 acid bilayers 1659 02:15:46,669 --> 02:15:44,460 for something like sodium potassium it's 1660 02:15:48,410 --> 02:15:46,679 significantly less permeable and like 1661 02:15:50,390 --> 02:15:48,420 over this scale that that's a really 1662 02:15:52,370 --> 02:15:50,400 significant margin there 1663 02:15:55,250 --> 02:15:52,380 and then for something like amp and 1664 02:15:57,050 --> 02:15:55,260 magnesium that's not actually on the 1665 02:15:58,850 --> 02:15:57,060 scale shown here for phospholipids so 1666 02:16:00,770 --> 02:15:58,860 it's way less permeable in phospholipid 1667 02:16:02,149 --> 02:16:00,780 membranes than it is in fatty acid 1668 02:16:03,830 --> 02:16:02,159 membranes 1669 02:16:06,530 --> 02:16:03,840 so again these results are particularly 1670 02:16:08,330 --> 02:16:06,540 surprising but I still wanted to try and 1671 02:16:10,970 --> 02:16:08,340 find a way to actually get these 1672 02:16:12,589 --> 02:16:10,980 nutrients to permeate the bilayer so 1673 02:16:14,330 --> 02:16:12,599 today I'm going to talk about a couple 1674 02:16:16,790 --> 02:16:14,340 of different strategies I've tried to 1675 02:16:18,830 --> 02:16:16,800 use to actually improve permeability the 1676 02:16:20,689 --> 02:16:18,840 first of which is modifying the membrane 1677 02:16:22,609 --> 02:16:20,699 composition 1678 02:16:25,129 --> 02:16:22,619 so as I said all the vesicles I've been 1679 02:16:28,010 --> 02:16:25,139 working with so far have been composed 1680 02:16:29,450 --> 02:16:28,020 of prbc and papg now these lipids are 1681 02:16:31,069 --> 02:16:29,460 quite nice to work with they're 1682 02:16:32,810 --> 02:16:31,079 cylindrical in shape so they're packed 1683 02:16:34,849 --> 02:16:32,820 together in these really nice bilayers 1684 02:16:37,370 --> 02:16:34,859 they're very uniform but what would 1685 02:16:38,929 --> 02:16:37,380 happen if I were to say disrupt the way 1686 02:16:41,750 --> 02:16:38,939 the lipid molecules actually pack 1687 02:16:43,969 --> 02:16:41,760 together what if I introduced a leopard 1688 02:16:46,969 --> 02:16:43,979 with a different shape something like 1689 02:16:49,190 --> 02:16:46,979 laser PC which has the single carbon 1690 02:16:51,169 --> 02:16:49,200 chain rather than two but it still has a 1691 02:16:53,389 --> 02:16:51,179 relatively bulky head group so it has 1692 02:16:55,250 --> 02:16:53,399 this more conical like shape and when 1693 02:16:57,589 --> 02:16:55,260 that gets inserted into bilayers it can 1694 02:16:59,389 --> 02:16:57,599 cause defects to form and pores which 1695 02:17:01,310 --> 02:16:59,399 would potentially allow nutrients to 1696 02:17:02,929 --> 02:17:01,320 pass through the membrane so I wanted to 1697 02:17:05,270 --> 02:17:02,939 explore what effect adding small 1698 02:17:06,830 --> 02:17:05,280 quantities of lyso PC would have on 1699 02:17:09,349 --> 02:17:06,840 permeability 1700 02:17:11,870 --> 02:17:09,359 and the other lipid I looked at is oleic 1701 02:17:14,150 --> 02:17:11,880 acid which is a fatty acid has a single 1702 02:17:16,129 --> 02:17:14,160 carbon chain and a relatively small head 1703 02:17:17,750 --> 02:17:16,139 group but because it's a fatty acid it 1704 02:17:20,150 --> 02:17:17,760 has a very different properties to what 1705 02:17:21,950 --> 02:17:20,160 phospholipids do so I wanted to explore 1706 02:17:25,910 --> 02:17:21,960 how those different properties might 1707 02:17:27,709 --> 02:17:25,920 affect the permeability of the membrane 1708 02:17:29,150 --> 02:17:27,719 and generally I found that they didn't 1709 02:17:31,969 --> 02:17:29,160 make much of a difference 1710 02:17:34,129 --> 02:17:31,979 so first of all I prepared all the 1711 02:17:37,129 --> 02:17:34,139 vesicles the same way I did before but 1712 02:17:40,070 --> 02:17:37,139 added about 10 either lyso PC or oleic 1713 02:17:42,650 --> 02:17:40,080 acid to the system and generally as I 1714 02:17:44,209 --> 02:17:42,660 said didn't make much of a difference we 1715 02:17:46,490 --> 02:17:44,219 have one of our example permeable 1716 02:17:48,709 --> 02:17:46,500 solutes there so glucose which we saw 1717 02:17:50,089 --> 02:17:48,719 was permeable earlier we can see in 1718 02:17:52,070 --> 02:17:50,099 those three curves there isn't really 1719 02:17:53,929 --> 02:17:52,080 much difference between them if anything 1720 02:17:56,150 --> 02:17:53,939 the green curve the oleic acid is 1721 02:17:57,770 --> 02:17:56,160 shifted down slightly but the shapes of 1722 02:17:59,690 --> 02:17:57,780 the curves are all very similar which is 1723 02:18:01,730 --> 02:17:59,700 telling us that the permeability hasn't 1724 02:18:03,709 --> 02:18:01,740 really changed and we see something 1725 02:18:06,469 --> 02:18:03,719 simple similar with one of the 1726 02:18:08,030 --> 02:18:06,479 impermeable solutes that being lysine I 1727 02:18:10,009 --> 02:18:08,040 still have all those flat lines so we 1728 02:18:12,709 --> 02:18:10,019 saw no improvement in permeability there 1729 02:18:13,969 --> 02:18:12,719 and this was generally the case across a 1730 02:18:15,830 --> 02:18:13,979 lot of the different solutes or 1731 02:18:17,389 --> 02:18:15,840 nutrients that I actually tried there 1732 02:18:20,150 --> 02:18:17,399 weren't any marked improvements in 1733 02:18:21,950 --> 02:18:20,160 permeability except for when I tried 1734 02:18:24,770 --> 02:18:21,960 sodium acetate 1735 02:18:27,410 --> 02:18:24,780 so when we had the presence of 10 a lake 1736 02:18:29,209 --> 02:18:27,420 acid in the system we see a significant 1737 02:18:31,730 --> 02:18:29,219 Improvement in permeability compared to 1738 02:18:34,070 --> 02:18:31,740 what it was originally with the popcpg 1739 02:18:36,530 --> 02:18:34,080 system and also compared to adding the 1740 02:18:38,270 --> 02:18:36,540 10th Cent lyso PC so we do see that 1741 02:18:39,830 --> 02:18:38,280 curve that's telling us that the vesicle 1742 02:18:41,629 --> 02:18:39,840 is swelling up again and we actually 1743 02:18:45,650 --> 02:18:41,639 have the solute molecules permeating 1744 02:18:48,230 --> 02:18:45,660 into the vesicle which is good news we 1745 02:18:50,030 --> 02:18:48,240 saw one of these uh solutes actually 1746 02:18:52,730 --> 02:18:50,040 kind of worked and actually were able to 1747 02:18:54,290 --> 02:18:52,740 permeate the membrane and as I said it 1748 02:18:55,969 --> 02:18:54,300 was great to see that it did work with 1749 02:18:58,129 --> 02:18:55,979 sodium acetate because we wanted to use 1750 02:19:00,589 --> 02:18:58,139 that as our carbon source for fatty acid 1751 02:19:02,150 --> 02:19:00,599 synthesis then phospholipid synthesis 1752 02:19:04,009 --> 02:19:02,160 and that would actually help getting the 1753 02:19:05,690 --> 02:19:04,019 membrane to grow 1754 02:19:07,429 --> 02:19:05,700 but as I said overall it didn't work for 1755 02:19:10,250 --> 02:19:07,439 a lot of the stuff I tried so I wanted 1756 02:19:12,049 --> 02:19:10,260 to try a second strategy to try and 1757 02:19:14,750 --> 02:19:12,059 improve permeability and that was 1758 02:19:16,370 --> 02:19:14,760 through the addition of divalent cations 1759 02:19:18,349 --> 02:19:16,380 so in literature it's pretty well 1760 02:19:20,330 --> 02:19:18,359 established that divalent cations also 1761 02:19:22,129 --> 02:19:20,340 affect the packing of the way of the 1762 02:19:24,169 --> 02:19:22,139 lipid molecules so the way the bilayers 1763 02:19:25,310 --> 02:19:24,179 actually packed together so I wanted to 1764 02:19:26,690 --> 02:19:25,320 see if that would make a difference to 1765 02:19:29,089 --> 02:19:26,700 permeability 1766 02:19:30,950 --> 02:19:29,099 and again generally I found it didn't 1767 02:19:34,190 --> 02:19:30,960 make that much of a difference except 1768 02:19:37,129 --> 02:19:34,200 for the presence of sodium acetate so 1769 02:19:39,169 --> 02:19:37,139 with the 10 Lake acid system and the 1770 02:19:41,270 --> 02:19:39,179 sodium acetate when I added magnesium 1771 02:19:43,429 --> 02:19:41,280 chloride which is what we see in the 1772 02:19:45,169 --> 02:19:43,439 orange there was a Improvement in 1773 02:19:46,969 --> 02:19:45,179 permeability if we see that curve kind 1774 02:19:48,710 --> 02:19:46,979 of increases faster than what the the 1775 02:19:50,870 --> 02:19:48,720 blue line which is just the pure sodium 1776 02:19:53,030 --> 02:19:50,880 acetate and the green line which is just 1777 02:19:54,830 --> 02:19:53,040 the magnesium chloride so for whatever 1778 02:19:57,590 --> 02:19:54,840 reason the addition of magnesium 1779 02:19:59,690 --> 02:19:57,600 chloride with the sodium acetate and in 1780 02:20:02,210 --> 02:19:59,700 the temps in oleic acid system did 1781 02:20:04,910 --> 02:20:02,220 improve permeability overall 1782 02:20:06,469 --> 02:20:04,920 but again generally I found that this 1783 02:20:08,510 --> 02:20:06,479 was quite difficult to achieve in a lot 1784 02:20:10,190 --> 02:20:08,520 of the solutes I tried I've also tried 1785 02:20:11,389 --> 02:20:10,200 other divalent cations which I haven't 1786 02:20:14,690 --> 02:20:11,399 shown here 1787 02:20:17,870 --> 02:20:14,700 um in general it was pretty tough 1788 02:20:19,610 --> 02:20:17,880 so what does that mean overall so 1789 02:20:21,889 --> 02:20:19,620 generally I've found that permeability 1790 02:20:24,290 --> 02:20:21,899 can somewhat be modulated for specific 1791 02:20:26,990 --> 02:20:24,300 specific sites by changing the membrane 1792 02:20:29,150 --> 02:20:27,000 composition and divalent cations can 1793 02:20:31,969 --> 02:20:29,160 somewhat improve the permeability of 1794 02:20:33,889 --> 02:20:31,979 specific solutes but overall it was 1795 02:20:35,929 --> 02:20:33,899 pretty difficult to actually see any 1796 02:20:37,429 --> 02:20:35,939 marked improvements in permeability for 1797 02:20:40,190 --> 02:20:37,439 a lot of the different things I studied 1798 02:20:42,650 --> 02:20:40,200 so what does that mean for origins of 1799 02:20:44,510 --> 02:20:42,660 life well perhaps we needed protein 1800 02:20:46,790 --> 02:20:44,520 channels to actually co-evolve with 1801 02:20:48,770 --> 02:20:46,800 phospholipid synthesis as I mentioned 1802 02:20:50,450 --> 02:20:48,780 earlier fatty acid membranes are much 1803 02:20:52,190 --> 02:20:50,460 more permeable than phospholipid 1804 02:20:54,530 --> 02:20:52,200 membranes so if they were the first 1805 02:20:56,870 --> 02:20:54,540 protocell membranes they were able to 1806 02:20:58,490 --> 02:20:56,880 access nutrients a lot easier than 1807 02:20:59,870 --> 02:20:58,500 phospholipid membranes on their own 1808 02:21:01,730 --> 02:20:59,880 would be able to so we've probably 1809 02:21:04,490 --> 02:21:01,740 needed some sort of mechanism to 1810 02:21:06,469 --> 02:21:04,500 actually co-evolve with phospholipids as 1811 02:21:08,870 --> 02:21:06,479 they started to emerge 1812 02:21:10,490 --> 02:21:08,880 but this is a very much an ongoing 1813 02:21:12,050 --> 02:21:10,500 project I'm trying a lot of different 1814 02:21:14,330 --> 02:21:12,060 membrane compositions a lot of different 1815 02:21:16,190 --> 02:21:14,340 divalent cations and I'm still working 1816 02:21:18,170 --> 02:21:16,200 on other methods to kind of improve 1817 02:21:20,090 --> 02:21:18,180 permeability so hopefully in the future 1818 02:21:22,849 --> 02:21:20,100 I'll have some more definitive results 1819 02:21:25,790 --> 02:21:22,859 with some improvements in permeability 1820 02:21:28,250 --> 02:21:25,800 for a lot of other solutes too 1821 02:21:30,230 --> 02:21:28,260 so with that I'd like to acknowledge the 1822 02:21:32,330 --> 02:21:30,240 entire Land Group and my supervisor Anna 1823 02:21:33,889 --> 02:21:32,340 for all her support thank you to my 1824 02:21:35,810 --> 02:21:33,899 sources of funding and thank you to 1825 02:21:36,540 --> 02:21:35,820 everyone for listening 1826 02:21:41,590 --> 02:21:36,550 [Applause] 1827 02:21:49,550 --> 02:21:41,600 [Laughter] 1828 02:21:55,309 --> 02:21:52,849 thank you I am from Ohio University I 1829 02:21:58,550 --> 02:21:55,319 study in molecular biology I'm just 1830 02:22:01,910 --> 02:21:58,560 interested in the method that you use to 1831 02:22:04,730 --> 02:22:01,920 measure your membrane permeability is it 1832 02:22:07,969 --> 02:22:04,740 a patch clamp electrophysiology or what 1833 02:22:12,710 --> 02:22:07,979 so the technique I was using is 1834 02:22:16,910 --> 02:22:14,450 it's actually a measure of the changes 1835 02:22:19,309 --> 02:22:16,920 in volume but it's reliant on the fact 1836 02:22:21,110 --> 02:22:19,319 that with those changes in volume they 1837 02:22:23,690 --> 02:22:21,120 can only occur because the solute is 1838 02:22:25,190 --> 02:22:23,700 actually permeating the membrane so it's 1839 02:22:27,410 --> 02:22:25,200 actually a fluorescence-based technique 1840 02:22:29,030 --> 02:22:27,420 so I use a fluorine fluimeter or plate 1841 02:22:30,889 --> 02:22:29,040 radar depending on the experimental 1842 02:22:32,570 --> 02:22:30,899 setup I have going to actually measure 1843 02:22:35,030 --> 02:22:32,580 those changes in fluorescence over time 1844 02:22:37,130 --> 02:22:35,040 and from that you can calculate the 1845 02:22:39,050 --> 02:22:37,140 changes in volume which you can actually 1846 02:22:40,849 --> 02:22:39,060 then go on to work out permeability 1847 02:22:42,410 --> 02:22:40,859 coefficients from those curves which is 1848 02:22:44,570 --> 02:22:42,420 something I haven't done yet but you can 1849 02:22:46,370 --> 02:22:44,580 actually fit a model to that curve and 1850 02:22:47,090 --> 02:22:46,380 extract the permeability coefficients as 1851 02:22:50,630 --> 02:22:47,100 well 1852 02:22:53,389 --> 02:22:50,640 okay I'm I'm just actually thinking that 1853 02:22:55,610 --> 02:22:53,399 um if you can employ the patch Clump 1854 02:22:58,510 --> 02:22:55,620 electrophysiology method it can give 1855 02:23:01,010 --> 02:22:58,520 insight into like membrane polarity 1856 02:23:03,650 --> 02:23:01,020 hyperpolarization yeah which can also 1857 02:23:05,630 --> 02:23:03,660 give more insight on this yeah 100 in 1858 02:23:07,010 --> 02:23:05,640 this a few other techniques that I've 1859 02:23:09,170 --> 02:23:07,020 actually used as well that are quite 1860 02:23:10,370 --> 02:23:09,180 similar to that but I I didn't show them 1861 02:23:11,990 --> 02:23:10,380 in this presentation but I'm happy to 1862 02:23:14,690 --> 02:23:12,000 chat about 1863 02:23:17,870 --> 02:23:16,370 hi I'm Tim from University of 1864 02:23:19,969 --> 02:23:17,880 Wisconsin-Madison 1865 02:23:22,190 --> 02:23:19,979 um I was wondering uh do you think there 1866 02:23:24,770 --> 02:23:22,200 could be an effect of physical size or 1867 02:23:26,510 --> 02:23:24,780 specifically surface area on the degree 1868 02:23:28,610 --> 02:23:26,520 of permeability and if so did you like 1869 02:23:31,130 --> 02:23:28,620 control for size did you extrude your 1870 02:23:33,349 --> 02:23:31,140 vesicles I showed it good question yeah 1871 02:23:34,910 --> 02:23:33,359 so these vesicles for this system I'm 1872 02:23:36,889 --> 02:23:34,920 working with have all been extruded 1873 02:23:39,170 --> 02:23:36,899 through 50 nanometer pause 1874 02:23:41,210 --> 02:23:39,180 they're roughly 1875 02:23:44,570 --> 02:23:41,220 they're probably about 40 nanometers in 1876 02:23:47,210 --> 02:23:44,580 diameter for the most part it's a 1877 02:23:49,910 --> 02:23:47,220 relatively even distribution added to 1878 02:23:52,190 --> 02:23:49,920 DLS on pretty similar systems 1879 02:23:53,929 --> 02:23:52,200 um yeah that that's why I did extrude 1880 02:23:56,090 --> 02:23:53,939 because I would expect from the ability 1881 02:23:58,010 --> 02:23:56,100 to be affected by the size of the 1882 02:24:00,220 --> 02:23:58,020 vesicles 1883 02:24:08,270 --> 02:24:00,230 thank you very much Lauren thank you 1884 02:24:13,010 --> 02:24:09,889 thank you okay 1885 02:24:18,110 --> 02:24:13,020 our next speakers be jono abishir 1886 02:24:18,120 --> 02:24:24,670 [Music] 1887 02:24:29,809 --> 02:24:26,530 hello everyone 1888 02:24:31,730 --> 02:24:29,819 my name is jono Abshire I am a second 1889 02:24:34,070 --> 02:24:31,740 year PhD student at Portland State 1890 02:24:35,990 --> 02:24:34,080 University working in the center for 1891 02:24:37,610 --> 02:24:36,000 life in extreme environments 1892 02:24:39,950 --> 02:24:37,620 more specifically out of the extreme 1893 02:24:41,950 --> 02:24:39,960 virus lab and today I'll be giving you a 1894 02:24:44,389 --> 02:24:41,960 little bit of insight into Life In Hell 1895 02:24:46,790 --> 02:24:44,399 understanding the role of toxin 1896 02:24:48,590 --> 02:24:46,800 antitoxin systems in prokaryotic genomes 1897 02:24:52,429 --> 02:24:48,600 and their potential for virus host 1898 02:24:54,050 --> 02:24:52,439 coevolution tldr extreme organisms the 1899 02:24:55,370 --> 02:24:54,060 viruses that infect them and their 1900 02:24:57,530 --> 02:24:55,380 interactions in these extreme 1901 02:24:59,510 --> 02:24:57,540 environments and our journey kind of 1902 02:25:01,750 --> 02:24:59,520 begins right here so this is a personal 1903 02:25:04,010 --> 02:25:01,760 image of Lassen Volcanic National Park 1904 02:25:06,230 --> 02:25:04,020 it is one of the many areas on our 1905 02:25:07,790 --> 02:25:06,240 beautiful planet that is home to these 1906 02:25:09,650 --> 02:25:07,800 volcanic Hot Springs 1907 02:25:11,630 --> 02:25:09,660 this is one of the main sampling sites 1908 02:25:12,950 --> 02:25:11,640 of our a lab and while most people 1909 02:25:15,230 --> 02:25:12,960 wouldn't believe that there are things 1910 02:25:16,510 --> 02:25:15,240 living in this environment there 1911 02:25:18,710 --> 02:25:16,520 certainly are 1912 02:25:20,210 --> 02:25:18,720 specifically these microbes from hell 1913 02:25:22,250 --> 02:25:20,220 and I'll get back to these guys in just 1914 02:25:24,590 --> 02:25:22,260 a second but a little bit of background 1915 02:25:26,570 --> 02:25:24,600 about why we why we studied these 1916 02:25:28,130 --> 02:25:26,580 particular environments so these 1917 02:25:30,650 --> 02:25:28,140 volcanic Hot Springs are often 1918 02:25:32,929 --> 02:25:30,660 considered and understood to be analogs 1919 02:25:35,090 --> 02:25:32,939 for both for planets both outside and 1920 02:25:37,610 --> 02:25:35,100 inside of our solar system referring 1921 02:25:40,429 --> 02:25:37,620 back to some of the ancient Hot Springs 1922 02:25:42,410 --> 02:25:40,439 found recently on Mars which may or may 1923 02:25:44,809 --> 02:25:42,420 not have looked something like this 1924 02:25:47,630 --> 02:25:44,819 boiling Mud Pot that we find in Devil's 1925 02:25:49,670 --> 02:25:47,640 Kitchen at Lassen Volcanic National Park 1926 02:25:53,170 --> 02:25:49,680 getting back to the microbes one such 1927 02:25:55,910 --> 02:25:53,180 microbe is this micro right here 1928 02:25:57,950 --> 02:25:55,920 spherical cell known as sacralobus 1929 02:25:59,750 --> 02:25:57,960 olfactericus this is a scanning electron 1930 02:26:01,190 --> 02:25:59,760 microscope showing you the topology of 1931 02:26:04,610 --> 02:26:01,200 the cells 1932 02:26:07,370 --> 02:26:04,620 um coined s441 by our lab really thrives 1933 02:26:09,349 --> 02:26:07,380 and uh lives in these hot acidic 1934 02:26:13,610 --> 02:26:09,359 conditions with temperatures from around 1935 02:26:16,070 --> 02:26:13,620 70 to 75 to 80 degrees C and ph's of 1936 02:26:19,190 --> 02:26:16,080 around three to as low as one so these 1937 02:26:21,050 --> 02:26:19,200 really extreme environments and when we 1938 02:26:24,170 --> 02:26:21,060 think about these environments and the 1939 02:26:27,469 --> 02:26:24,180 reach ecosystems that uh and habitat 1940 02:26:30,530 --> 02:26:27,479 them we can also think about one of the 1941 02:26:32,450 --> 02:26:30,540 most abundant molecules on the planet so 1942 02:26:34,670 --> 02:26:32,460 that of viruses and yes there are these 1943 02:26:37,010 --> 02:26:34,680 extreme viruses infecting these 1944 02:26:39,050 --> 02:26:37,020 extremophiles uh the one which I work 1945 02:26:41,330 --> 02:26:39,060 with in lab is sopholobus spindle shape 1946 02:26:44,630 --> 02:26:41,340 virus one sacralobus is a natural host 1947 02:26:46,550 --> 02:26:44,640 of this particular virus this ssv1 this 1948 02:26:49,309 --> 02:26:46,560 is Stanley uses they them pronouns 1949 02:26:51,230 --> 02:26:49,319 really characterized by his lemon shape 1950 02:26:53,450 --> 02:26:51,240 so these shapes are really unique to 1951 02:26:56,450 --> 02:26:53,460 both archaeal organisms extremophiles 1952 02:26:58,429 --> 02:26:56,460 and some of these extreme viruses 1953 02:27:00,050 --> 02:26:58,439 and when we think about looking at these 1954 02:27:02,270 --> 02:27:00,060 organisms and the interactions between 1955 02:27:03,950 --> 02:27:02,280 them in these extreme environments we 1956 02:27:06,830 --> 02:27:03,960 can look at some systems currently 1957 02:27:10,309 --> 02:27:06,840 prevalent today in bacterial cells so 1958 02:27:13,010 --> 02:27:10,319 these toxin antitoxin systems usually 1959 02:27:15,469 --> 02:27:13,020 known as addiction modules found on 1960 02:27:19,370 --> 02:27:15,479 plasmids again really prevalent in 1961 02:27:22,429 --> 02:27:19,380 bacterial genomes only recently being 1962 02:27:24,050 --> 02:27:22,439 being discovered to have some viral 1963 02:27:27,349 --> 02:27:24,060 encoding 1964 02:27:30,290 --> 02:27:27,359 and what this particular system confers 1965 02:27:32,210 --> 02:27:30,300 is when you have a plasmid that has the 1966 02:27:34,790 --> 02:27:32,220 positive uh or is positive for that 1967 02:27:36,590 --> 02:27:34,800 particular addiction module that cell 1968 02:27:38,450 --> 02:27:36,600 will needs that plasmid in order to 1969 02:27:40,910 --> 02:27:38,460 continue its life in that particular 1970 02:27:42,170 --> 02:27:40,920 environment so here we have the presence 1971 02:27:44,510 --> 02:27:42,180 of the TA 1972 02:27:47,030 --> 02:27:44,520 um should that cell or progeny continue 1973 02:27:48,230 --> 02:27:47,040 with the presence of that plasmid you 1974 02:27:50,150 --> 02:27:48,240 would expect normal growth in the 1975 02:27:51,950 --> 02:27:50,160 environment whereas if it were to lose 1976 02:27:54,349 --> 02:27:51,960 that plasmid it would would have been 1977 02:27:55,910 --> 02:27:54,359 addicted to that particular genome it 1978 02:27:57,889 --> 02:27:55,920 would die off whereas in a negative 1979 02:28:00,230 --> 02:27:57,899 system you would get growth either way 1980 02:28:02,150 --> 02:28:00,240 whether or not there's plasmid loss and 1981 02:28:04,010 --> 02:28:02,160 we can further visualize this particular 1982 02:28:06,830 --> 02:28:04,020 mechanism by looking at what might 1983 02:28:08,750 --> 02:28:06,840 happen to some uncolonized cells some 1984 02:28:10,610 --> 02:28:08,760 sort of event happens in which the 1985 02:28:11,990 --> 02:28:10,620 addiction modules introduced to that 1986 02:28:13,910 --> 02:28:12,000 population 1987 02:28:16,130 --> 02:28:13,920 and you have your addicted Survivor 1988 02:28:17,750 --> 02:28:16,140 going on to make new progeny and then 1989 02:28:20,150 --> 02:28:17,760 conferring that group protection and 1990 02:28:23,030 --> 02:28:20,160 persistence so these systems are really 1991 02:28:26,389 --> 02:28:23,040 understood in bacteria to confer a 1992 02:28:29,210 --> 02:28:26,399 microbial persistence phenotype some 1993 02:28:32,389 --> 02:28:29,220 have been referred to as fate defense 1994 02:28:36,110 --> 02:28:32,399 mechanisms and largely considered as 1995 02:28:38,210 --> 02:28:36,120 plasmid stabilizers on the plasmin 1996 02:28:39,889 --> 02:28:38,220 um and we can also uh assume that 1997 02:28:41,150 --> 02:28:39,899 another group of uncolonized cells were 1998 02:28:43,070 --> 02:28:41,160 to come in here perhaps that group 1999 02:28:45,830 --> 02:28:43,080 encounter you would still get that toxic 2000 02:28:48,110 --> 02:28:45,840 culling uh from that toxin antitoxin 2001 02:28:49,910 --> 02:28:48,120 system uh one important note they are 2002 02:28:52,130 --> 02:28:49,920 characterized as two genes that are 2003 02:28:54,590 --> 02:28:52,140 typically right next to each other 2004 02:28:57,110 --> 02:28:54,600 um the toxin being just Downstream of 2005 02:28:59,929 --> 02:28:57,120 the antitoxin uh pretty stable toxin 2006 02:29:02,450 --> 02:28:59,939 pretty unstable antitoxin 2007 02:29:04,250 --> 02:29:02,460 and looking at this system with ssv1 a 2008 02:29:09,410 --> 02:29:04,260 previous student did quite a bit of work 2009 02:29:11,510 --> 02:29:09,420 in uh mutagenesis of the ssv1 genome and 2010 02:29:14,090 --> 02:29:11,520 we use this at least these mutants to 2011 02:29:15,530 --> 02:29:14,100 test whether or not some of these uh 2012 02:29:18,050 --> 02:29:15,540 genes or open reading frames are 2013 02:29:20,750 --> 02:29:18,060 essential to the virus and two genes in 2014 02:29:22,910 --> 02:29:20,760 particular this T3 and TX transcript 2015 02:29:25,969 --> 02:29:22,920 these particular two genes we can make 2016 02:29:29,690 --> 02:29:25,979 changes to what I think is the antitoxin 2017 02:29:31,910 --> 02:29:29,700 and we don't see too much difference in 2018 02:29:34,429 --> 02:29:31,920 terms of viral infection viral function 2019 02:29:36,410 --> 02:29:34,439 whereas if we were to delete this or 2020 02:29:38,150 --> 02:29:36,420 insert a sequence into this particular 2021 02:29:41,270 --> 02:29:38,160 open reading frame what I think is the 2022 02:29:42,950 --> 02:29:41,280 toxin we do see differences in infection 2023 02:29:47,450 --> 02:29:42,960 mechanisms 2024 02:29:49,370 --> 02:29:47,460 these extreme viruses and just virus 2025 02:29:51,889 --> 02:29:49,380 reproduction overall viruses can 2026 02:29:54,349 --> 02:29:51,899 typically go through two Pathways or a 2027 02:29:57,230 --> 02:29:54,359 combination of both so a lytic cycle in 2028 02:29:58,969 --> 02:29:57,240 which the viral genome the viral DNA 2029 02:30:01,190 --> 02:29:58,979 will insert itself into the cell 2030 02:30:03,889 --> 02:30:01,200 you have some replication going on 2031 02:30:06,050 --> 02:30:03,899 eventually assembly of those virions and 2032 02:30:07,969 --> 02:30:06,060 the cell will then burst die and those 2033 02:30:10,849 --> 02:30:07,979 viruses will go on to infect other cells 2034 02:30:13,130 --> 02:30:10,859 whereas in a lysogenic cycle the viral 2035 02:30:15,230 --> 02:30:13,140 genome is incorporated into the host 2036 02:30:17,510 --> 02:30:15,240 genome and there's usually a latent 2037 02:30:20,410 --> 02:30:17,520 phase in which it kind of just stays 2038 02:30:24,110 --> 02:30:20,420 there maybe some induction event happens 2039 02:30:26,690 --> 02:30:24,120 in ssv's case it actually just buds from 2040 02:30:28,429 --> 02:30:26,700 the cell without killing the cell and 2041 02:30:31,130 --> 02:30:28,439 one of the one of the two ways that we 2042 02:30:33,530 --> 02:30:31,140 use to test for this viral reproduction 2043 02:30:35,870 --> 02:30:33,540 is of course PCR so amplifying a 2044 02:30:38,469 --> 02:30:35,880 sequence that's specific to viral DNA 2045 02:30:42,110 --> 02:30:38,479 looking for its presence in cell-free 2046 02:30:44,090 --> 02:30:42,120 supernatants another way is through Halo 2047 02:30:45,590 --> 02:30:44,100 assay so very similar to a plaque assay 2048 02:30:46,550 --> 02:30:45,600 in which you look where cells are 2049 02:30:50,030 --> 02:30:46,560 bursting 2050 02:30:52,130 --> 02:30:50,040 we cultivate a lot of cells uninfected 2051 02:30:54,830 --> 02:30:52,140 sacroilobus cells like you saw in the 2052 02:30:56,870 --> 02:30:54,840 slide a while back and then we spot cell 2053 02:30:58,370 --> 02:30:56,880 free supernatants which contain these 2054 02:31:00,950 --> 02:30:58,380 mutant viruses 2055 02:31:03,830 --> 02:31:00,960 onto the plate and look for clearings 2056 02:31:06,830 --> 02:31:03,840 and this Halo assay is made possible 2057 02:31:10,070 --> 02:31:06,840 because of the fact that ssv1 buds from 2058 02:31:12,469 --> 02:31:10,080 its cell without killing the cell 2059 02:31:14,510 --> 02:31:12,479 um and the UN the infected cells grow 2060 02:31:16,910 --> 02:31:14,520 quite slower so it really converts this 2061 02:31:18,830 --> 02:31:16,920 growth stunting phenotype in the 2062 02:31:21,290 --> 02:31:18,840 sacrolobus cell 2063 02:31:23,030 --> 02:31:21,300 and looking at the toxin protein and 2064 02:31:24,469 --> 02:31:23,040 large a large majority of my work has 2065 02:31:28,370 --> 02:31:24,479 been looking at mutants that we've made 2066 02:31:30,290 --> 02:31:28,380 in this toxin protein and several uh 2067 02:31:31,910 --> 02:31:30,300 machine learning softwares have 2068 02:31:35,330 --> 02:31:31,920 indicated that there's a quite a high 2069 02:31:37,849 --> 02:31:35,340 probability of a cleavage site over here 2070 02:31:40,849 --> 02:31:37,859 behind this very hydrophobic 2071 02:31:42,469 --> 02:31:40,859 uh helicy right here and so I sought to 2072 02:31:45,710 --> 02:31:42,479 characterize at least this particular 2073 02:31:47,929 --> 02:31:45,720 mechanism in ssv1 through using some of 2074 02:31:51,530 --> 02:31:47,939 these mutants that we already have 2075 02:31:53,150 --> 02:31:51,540 um and while largely these over here are 2076 02:31:55,370 --> 02:31:53,160 our wild type so really shouldn't expect 2077 02:31:58,309 --> 02:31:55,380 any kind of change in viral function you 2078 02:32:01,130 --> 02:31:58,319 can see some really nice Halos and we 2079 02:32:03,170 --> 02:32:01,140 can confer that you know the cells are 2080 02:32:04,849 --> 02:32:03,180 not dying but they're sick 2081 02:32:08,630 --> 02:32:04,859 and in our mutants where we have 2082 02:32:10,790 --> 02:32:08,640 insertions in in that specific toxin uh 2083 02:32:12,410 --> 02:32:10,800 open reading frame we don't see any Halo 2084 02:32:15,469 --> 02:32:12,420 formation 2085 02:32:17,870 --> 02:32:15,479 um likewise I sought to substitute those 2086 02:32:20,570 --> 02:32:17,880 two uh residues at the cleavage site 2087 02:32:23,510 --> 02:32:20,580 since it's largely important for protein 2088 02:32:25,370 --> 02:32:23,520 maturation protein function and we still 2089 02:32:28,309 --> 02:32:25,380 don't see a Halo just switching those 2090 02:32:30,050 --> 02:32:28,319 two residues but the main takeaway from 2091 02:32:33,650 --> 02:32:30,060 this is that we still get virus 2092 02:32:35,450 --> 02:32:33,660 replication we still get quite a bit of 2093 02:32:37,210 --> 02:32:35,460 at least high levels of viral 2094 02:32:40,070 --> 02:32:37,220 replication from some of these mutants 2095 02:32:42,130 --> 02:32:40,080 and one of these mutants particular we 2096 02:32:43,969 --> 02:32:42,140 didn't see anything so maybe that one's 2097 02:32:46,730 --> 02:32:43,979 detrimental to that particular open 2098 02:32:49,309 --> 02:32:46,740 reading frame but we do see that there 2099 02:32:52,730 --> 02:32:49,319 is virus replication happening in the 2100 02:32:55,610 --> 02:32:52,740 cell supernatant when we screen for DNA 2101 02:32:57,830 --> 02:32:55,620 and it's important to kind of note that 2102 02:33:01,070 --> 02:32:57,840 this this protein isn't just unique to 2103 02:33:03,530 --> 02:33:01,080 ssv1 in in looking at these systems in 2104 02:33:05,570 --> 02:33:03,540 these extreme organisms uh this one in 2105 02:33:08,030 --> 02:33:05,580 particular up here is another SSV so 2106 02:33:10,070 --> 02:33:08,040 another spindle shape virus in which we 2107 02:33:13,250 --> 02:33:10,080 see really low sequence similarity 2108 02:33:15,469 --> 02:33:13,260 across these particular genes but quite 2109 02:33:17,570 --> 02:33:15,479 a hot quite a high bit of 2110 02:33:20,290 --> 02:33:17,580 um structural similarity between these 2111 02:33:23,090 --> 02:33:20,300 genes and a lot of these are 2112 02:33:25,969 --> 02:33:23,100 genomes of extremophiles while some are 2113 02:33:28,309 --> 02:33:25,979 virally encoded 2114 02:33:30,230 --> 02:33:28,319 and uh one of the main takeaways really 2115 02:33:32,030 --> 02:33:30,240 just wrapping uh wrapping it all back 2116 02:33:33,889 --> 02:33:32,040 around looking for these particular 2117 02:33:35,570 --> 02:33:33,899 mechanisms and how they confer 2118 02:33:38,389 --> 02:33:35,580 persistence with both their 2119 02:33:41,090 --> 02:33:38,399 extremophilic organism and their viruses 2120 02:33:43,389 --> 02:33:41,100 would be a really nice first start in 2121 02:33:47,570 --> 02:33:43,399 looking for these biosignatures perhaps 2122 02:33:49,670 --> 02:33:47,580 and ways that we can look into how the 2123 02:33:51,710 --> 02:33:49,680 microbes might be interacting 2124 02:33:53,870 --> 02:33:51,720 in these particular extreme environments 2125 02:33:56,270 --> 02:33:53,880 this is another sampling video 2126 02:33:58,790 --> 02:33:56,280 um just of last in volcanic Park pretty 2127 02:34:00,110 --> 02:33:58,800 pretty close to where s441 was isolated 2128 02:34:02,210 --> 02:34:00,120 from 2129 02:34:04,010 --> 02:34:02,220 uh looks pretty similar to maybe 2130 02:34:05,750 --> 02:34:04,020 something we'd see on another planet 2131 02:34:09,349 --> 02:34:05,760 that we could sample at 2132 02:34:11,330 --> 02:34:09,359 and then a Shameless plug but looking 2133 02:34:12,950 --> 02:34:11,340 for viruses in space I think is the 2134 02:34:14,950 --> 02:34:12,960 obvious next step we know that they're 2135 02:34:18,290 --> 02:34:14,960 the most abundant molecule in the planet 2136 02:34:19,910 --> 02:34:18,300 and just understanding that these 2137 02:34:22,429 --> 02:34:19,920 mechanisms and that these systems are 2138 02:34:25,130 --> 02:34:22,439 out there allowing these cells to thrive 2139 02:34:28,309 --> 02:34:25,140 in this particular environment would be 2140 02:34:30,950 --> 02:34:28,319 a great uh in starter conversation for 2141 02:34:32,090 --> 02:34:30,960 looking for these small biomolecules in 2142 02:34:34,309 --> 02:34:32,100 space 2143 02:34:35,690 --> 02:34:34,319 and with that I just want to thank my 2144 02:34:38,330 --> 02:34:35,700 loud 2145 02:34:41,450 --> 02:34:38,340 um my group over here at Boiling Springs 2146 02:34:50,929 --> 02:34:41,460 Lake when we collected samples and my Pi 2147 02:34:58,130 --> 02:34:53,090 thank you General we have a time for 2148 02:35:02,150 --> 02:35:00,230 hey my name is Pia and I'm really 2149 02:35:03,530 --> 02:35:02,160 interested in like crispr costume Unity 2150 02:35:05,030 --> 02:35:03,540 of microbes 2151 02:35:06,830 --> 02:35:05,040 um have you looked at all into the 2152 02:35:08,030 --> 02:35:06,840 interactions of other phage defense 2153 02:35:11,990 --> 02:35:08,040 systems 2154 02:35:14,330 --> 02:35:12,000 um yeah so at least in terms of uh this 2155 02:35:16,550 --> 02:35:14,340 toxin antitoxin system they're pretty 2156 02:35:18,050 --> 02:35:16,560 understood in bacterial cells to like 2157 02:35:21,530 --> 02:35:18,060 incorporate themselves into the genomic 2158 02:35:23,990 --> 02:35:21,540 crispr cas9 there are some proteins that 2159 02:35:25,790 --> 02:35:24,000 um that look pretty similar to this a291 2160 02:35:29,870 --> 02:35:25,800 and some of these other virally encoded 2161 02:35:33,410 --> 02:35:29,880 genes that do have some kind of crispr 2162 02:35:35,270 --> 02:35:33,420 casts editing mechanism so yeah I think 2163 02:35:36,710 --> 02:35:35,280 they it might be leaning towards that 2164 02:35:38,929 --> 02:35:36,720 way but they're pretty well 2165 02:35:41,630 --> 02:35:38,939 characterized in terms of like how they 2166 02:35:43,790 --> 02:35:41,640 work with proteins and mRNA so um yeah 2167 02:35:45,410 --> 02:35:43,800 not too far there yet but 2168 02:35:58,969 --> 02:35:45,420 um definitely definitely somewhere in 2169 02:36:04,670 --> 02:36:01,130 uh thank you for the talk Marshall 2170 02:36:06,290 --> 02:36:04,680 Seaton JPL and I I was curious so um 2171 02:36:08,450 --> 02:36:06,300 you're talking about looking for viruses 2172 02:36:10,070 --> 02:36:08,460 and extraterrestrial environments um do 2173 02:36:12,110 --> 02:36:10,080 you think there would be or I'm curious 2174 02:36:14,750 --> 02:36:12,120 I'm completely ignorant yeah no no I 2175 02:36:17,210 --> 02:36:14,760 dropped out of Bio too so for this 2176 02:36:20,090 --> 02:36:17,220 um for viruses specifically like would 2177 02:36:22,550 --> 02:36:20,100 small molecule biosignature classes vary 2178 02:36:25,730 --> 02:36:22,560 from viruses to like what you'd be 2179 02:36:27,950 --> 02:36:25,740 looking for with cells yeah yeah I I for 2180 02:36:29,270 --> 02:36:27,960 sure and that kind of brings me at least 2181 02:36:31,250 --> 02:36:29,280 back to a point like of looking for 2182 02:36:32,990 --> 02:36:31,260 fossils and stuff like that so viruses 2183 02:36:35,030 --> 02:36:33,000 and sediment 2184 02:36:37,309 --> 02:36:35,040 um and at least our lab there's been 2185 02:36:39,349 --> 02:36:37,319 some work in like silica and coding 2186 02:36:41,809 --> 02:36:39,359 viruses and how you know the stability 2187 02:36:43,790 --> 02:36:41,819 of them so maybe there's a pretty silica 2188 02:36:45,590 --> 02:36:43,800 Rich environment in which we might be 2189 02:36:47,750 --> 02:36:45,600 able to look for any kind of these 2190 02:36:50,389 --> 02:36:47,760 signatures so like proteins 2191 02:36:52,010 --> 02:36:50,399 um or or yeah just specific things that 2192 02:36:54,590 --> 02:36:52,020 might might have been preserved in those 2193 02:36:57,050 --> 02:36:54,600 particular environments considering that 2194 02:36:58,610 --> 02:36:57,060 these viruses live and thrive in in 2195 02:37:00,830 --> 02:36:58,620 pretty extremes 2196 02:37:02,150 --> 02:37:00,840 um you know they're they're they got to 2197 02:37:04,910 --> 02:37:02,160 be out there at least 2198 02:37:07,070 --> 02:37:04,920 and so you mentioned um uh looking at 2199 02:37:09,469 --> 02:37:07,080 like morphology and fossils and things 2200 02:37:11,690 --> 02:37:09,479 like that I know that at least for 2201 02:37:13,790 --> 02:37:11,700 um looking at cells and things 2202 02:37:16,429 --> 02:37:13,800 um they've been shown to to mimic 2203 02:37:18,469 --> 02:37:16,439 abiotic systems uh pretty well because 2204 02:37:22,190 --> 02:37:18,479 humans are very good pattern recognition 2205 02:37:23,830 --> 02:37:22,200 and so um has anything been seen like 2206 02:37:28,070 --> 02:37:23,840 that for viruses 2207 02:37:29,630 --> 02:37:28,080 yeah not that not that I'm familiar with 2208 02:37:31,550 --> 02:37:29,640 um I know it's at least a brand new 2209 02:37:33,710 --> 02:37:31,560 conversation of starting to look for 2210 02:37:36,050 --> 02:37:33,720 like viruses in space Astro virology 2211 02:37:38,150 --> 02:37:36,060 things like that so uh yeah we're just 2212 02:37:39,410 --> 02:37:38,160 kind of getting up and running oh yeah 2213 02:37:41,150 --> 02:37:39,420 yeah no sorry I don't mean to like play 2214 02:37:47,750 --> 02:37:41,160 20 Questions oh no no I just thought it 2215 02:37:52,010 --> 02:37:50,210 yeah yeah there's a there's a little 2216 02:37:54,050 --> 02:37:52,020 cure lab that like goes on right now 2217 02:37:58,910 --> 02:37:54,060 that I teach so I'm obviously not there 2218 02:37:58,920 --> 02:38:06,220 any other questions 2219 02:38:17,389 --> 02:38:13,610 [Applause] 2220 02:38:26,020 --> 02:38:17,399 our next speaker is Fatima liho from the 2221 02:39:11,650 --> 02:38:40,010 [Music] 2222 02:39:27,320 --> 02:39:13,920 thank you 2223 02:39:27,330 --> 02:39:31,010 [Music] 2224 02:39:31,020 --> 02:39:36,540 foreign 2225 02:40:23,630 --> 02:39:46,330 [Music] 2226 02:40:23,640 --> 02:40:32,200 thank you 2227 02:40:53,950 --> 02:40:40,110 [Music] 2228 02:41:03,340 --> 02:40:53,960 foreign 2229 02:41:53,330 --> 02:41:16,040 [Music] 2230 02:41:53,340 --> 02:41:57,500 thank you 2231 02:42:08,220 --> 02:42:04,530 [Music] 2232 02:42:20,770 --> 02:42:08,230 foreign 2233 02:42:51,710 --> 02:42:26,290 [Music] 2234 02:42:51,720 --> 02:42:57,190 foreign 2235 02:43:18,390 --> 02:43:13,970 [Music] 2236 02:43:33,010 --> 02:43:18,400 foreign 2237 02:44:03,490 --> 02:43:40,140 [Music] 2238 02:44:27,349 --> 02:44:05,290 thank you 2239 02:45:41,290 --> 02:44:27,359 [Music] 2240 02:45:46,849 --> 02:45:42,650 thank you 2241 02:46:08,630 --> 02:45:49,120 foreign 2242 02:46:33,250 --> 02:46:15,020 [Music] 2243 02:47:12,429 --> 02:46:34,580 thank you 2244 02:47:51,070 --> 02:47:12,439 [Music] 2245 02:47:58,850 --> 02:47:52,390 thank you 2246 02:49:01,480 --> 02:48:20,870 [Music] 2247 02:49:17,420 --> 02:49:01,490 thank you 2248 02:49:17,430 --> 02:49:38,389 [Music] 2249 02:49:38,399 --> 02:49:42,630 foreign 2250 02:50:27,490 --> 02:50:09,310 [Music] 2251 02:50:27,500 --> 02:50:35,280 thank you 2252 02:50:35,290 --> 02:50:58,190 [Music] 2253 02:51:19,920 --> 02:51:00,390 foreign 2254 02:51:42,849 --> 02:51:27,150 [Music] 2255 02:51:42,859 --> 02:51:49,510 Pena from Soma 2256 02:51:55,389 --> 02:51:53,929 hi everyone thank you for having me this 2257 02:51:58,010 --> 02:51:55,399 is a very special moment for me because 2258 02:52:00,530 --> 02:51:58,020 I am talking about going to talk about 2259 02:52:03,650 --> 02:52:00,540 hydrothermal dance so beans creeps have 2260 02:52:06,110 --> 02:52:03,660 is a very special moment so I'm happy to 2261 02:52:07,690 --> 02:52:06,120 share it with you and also about my PhD 2262 02:52:11,510 --> 02:52:07,700 Journey 2263 02:52:14,450 --> 02:52:11,520 so the link in hydrothermal veins is 2264 02:52:18,230 --> 02:52:14,460 very important between the the ocean 2265 02:52:21,950 --> 02:52:18,240 space Sciences since its Discovery in 2266 02:52:24,769 --> 02:52:21,960 the 70s the efforts to study the deep 2267 02:52:27,950 --> 02:52:24,779 ocean and these extreme environments has 2268 02:52:30,710 --> 02:52:27,960 increased a lot in these last years also 2269 02:52:32,570 --> 02:52:30,720 because of all the technology and all 2270 02:52:36,590 --> 02:52:32,580 the improvements that it has been made 2271 02:52:39,650 --> 02:52:36,600 through a study the deep sea and also 2272 02:52:42,910 --> 02:52:39,660 not only it was an outstanding Discovery 2273 02:52:45,530 --> 02:52:42,920 for your physicist geologists also for 2274 02:52:48,290 --> 02:52:45,540 biology and microbiologists that we 2275 02:52:50,809 --> 02:52:48,300 found these extreme ecosystems where we 2276 02:52:53,389 --> 02:52:50,819 are finding these extremophiles that are 2277 02:52:55,730 --> 02:52:53,399 high with high diversity not only 2278 02:52:58,490 --> 02:52:55,740 microbiology but also on microbiology 2279 02:53:01,309 --> 02:52:58,500 and in a bigger scope herothermal veins 2280 02:53:04,130 --> 02:53:01,319 are very important for astrobiology a 2281 02:53:06,070 --> 02:53:04,140 bigger scope is a origin of lightweight 2282 02:53:09,469 --> 02:53:06,080 is a very important thing in our planet 2283 02:53:12,110 --> 02:53:09,479 and also for looking 2284 02:53:14,389 --> 02:53:12,120 um live elsewhere also thermal van 2285 02:53:18,349 --> 02:53:14,399 systems has been proposed not only as 2286 02:53:21,910 --> 02:53:18,359 place where these structures have uh 2287 02:53:25,550 --> 02:53:21,920 have created or originated the molecules 2288 02:53:28,190 --> 02:53:25,560 for the cells but also for probably 2289 02:53:30,950 --> 02:53:28,200 there there are similar structures uh 2290 02:53:32,929 --> 02:53:30,960 existing in the icing wounds so this is 2291 02:53:36,110 --> 02:53:32,939 one of the biggest scope that we are 2292 02:53:38,450 --> 02:53:36,120 studying hydrothermal dance but a in 2293 02:53:40,250 --> 02:53:38,460 particular in this topic we are 2294 02:53:44,389 --> 02:53:40,260 exploring what is the Gulf of California 2295 02:53:46,790 --> 02:53:44,399 and Mexico so if you're will hit the 2296 02:53:49,429 --> 02:53:46,800 Gulf of California we are 2297 02:53:51,050 --> 02:53:49,439 here in Scripps out the north if you 2298 02:53:53,269 --> 02:53:51,060 cross the border here Tijuana and 2299 02:53:57,370 --> 02:53:53,279 Ensenada excellent tacos if you want to 2300 02:54:00,590 --> 02:53:57,380 stay longer you can tell me but for 2301 02:54:02,630 --> 02:54:00,600 studying the Gulf of California uh the 2302 02:54:05,050 --> 02:54:02,640 deep ocean has been studied for over a 2303 02:54:08,870 --> 02:54:05,060 decade and we have well they have found 2304 02:54:10,370 --> 02:54:08,880 that there is a series of transform 2305 02:54:11,150 --> 02:54:10,380 false 2306 02:54:14,090 --> 02:54:11,160 um 2307 02:54:15,830 --> 02:54:14,100 and spreading centers which have led to 2308 02:54:19,370 --> 02:54:15,840 the discovery of hydrothermal vent 2309 02:54:23,349 --> 02:54:19,380 systems in particular we have found here 2310 02:54:25,370 --> 02:54:23,359 it is uh impascular Basin at South 2311 02:54:27,290 --> 02:54:25,380 of the peninsula of the Gulf of 2312 02:54:29,090 --> 02:54:27,300 California we have found two 2313 02:54:32,090 --> 02:54:29,100 hydrothermaline systems I'm sorry they 2314 02:54:35,710 --> 02:54:32,100 they moved but here the yellow dot it's 2315 02:54:40,130 --> 02:54:35,720 called Alka and the Red Dot is called 2316 02:54:43,450 --> 02:54:40,140 Alka was discovered in 2015 and jagma 2317 02:54:46,790 --> 02:54:43,460 has were discovering 2018 2318 02:54:49,030 --> 02:54:46,800 these are the hierothermal band fields 2319 02:54:52,550 --> 02:54:49,040 that are at a depth of 2320 02:54:54,290 --> 02:54:52,560 3600 meters that this is the deepest 2321 02:54:56,450 --> 02:54:54,300 known halotemoral vein system in the 2322 02:54:59,349 --> 02:54:56,460 Pacific Ocean where it has levels to 2323 02:55:03,410 --> 02:54:59,359 study them as a very extreme ecosystem 2324 02:55:05,870 --> 02:55:03,420 and we have found that the the chemistry 2325 02:55:09,290 --> 02:55:05,880 of these harassment veins are it's very 2326 02:55:11,929 --> 02:55:09,300 unique they are made of calcite and they 2327 02:55:15,429 --> 02:55:11,939 have been some temperature measurements 2328 02:55:18,830 --> 02:55:15,439 of between the 20 degrees to 100 degrees 2329 02:55:20,870 --> 02:55:18,840 Celsius in around the 30 minutes but one 2330 02:55:25,670 --> 02:55:20,880 of the the highest hydrothermal veins 2331 02:55:28,610 --> 02:55:25,680 temperature goes around 300 degrees so 2332 02:55:29,990 --> 02:55:28,620 uh one of the questions that we have one 2333 02:55:31,730 --> 02:55:30,000 of the big questions that we have for 2334 02:55:34,429 --> 02:55:31,740 studying this hydrothermal vein systems 2335 02:55:36,710 --> 02:55:34,439 is who are the microbes related to the 2336 02:55:39,349 --> 02:55:36,720 hydrothermal fluids in the sediments of 2337 02:55:41,090 --> 02:55:39,359 the Alka and jagma Halo thermal band 2338 02:55:44,389 --> 02:55:41,100 feels because we don't know a lot of 2339 02:55:46,730 --> 02:55:44,399 these heart Hamilton systems so the 2340 02:55:47,570 --> 02:55:46,740 first question was who are them 2341 02:55:51,349 --> 02:55:47,580 um 2342 02:55:55,010 --> 02:55:51,359 so for this an oceanic oceanographic 2343 02:55:59,349 --> 02:55:55,020 expedition was made in 2018 about the 2344 02:56:03,410 --> 02:55:59,359 research vessel Falcor and this research 2345 02:56:07,429 --> 02:56:03,420 vessel has a ROV called Sebastian which 2346 02:56:10,010 --> 02:56:07,439 is a Rover that left us submerged and 2347 02:56:13,370 --> 02:56:10,020 with our robotic arm it had it was able 2348 02:56:15,469 --> 02:56:13,380 to take some samples of the sediments so 2349 02:56:17,150 --> 02:56:15,479 here you can see a little insight about 2350 02:56:19,429 --> 02:56:17,160 how are the sediments around this 2351 02:56:21,889 --> 02:56:19,439 hierothermal vents all the things all 2352 02:56:26,650 --> 02:56:21,899 the white stuff that you see around is 2353 02:56:29,710 --> 02:56:26,660 microbial mat so we collected around 30 2354 02:56:35,030 --> 02:56:29,720 push course sediments 2355 02:56:37,730 --> 02:56:35,040 and all these curl samples were section 2356 02:56:39,769 --> 02:56:37,740 um on the ship and it will stop 2357 02:56:44,269 --> 02:56:39,779 something with um 2358 02:56:46,730 --> 02:56:44,279 for taking DNA extraction to do poor 2359 02:56:48,590 --> 02:56:46,740 Water Analysis back in the lab we made 2360 02:56:52,370 --> 02:56:48,600 some iron chromatography DNA 2361 02:56:53,809 --> 02:56:52,380 amplification of 16s some sequencing and 2362 02:56:56,750 --> 02:56:53,819 bioinformatics and of course some 2363 02:56:58,730 --> 02:56:56,760 statistical analysis and so here I'm 2364 02:57:02,750 --> 02:56:58,740 going to present you some of the of the 2365 02:57:05,030 --> 02:57:02,760 results of of this so one of I'll the 2366 02:57:08,210 --> 02:57:05,040 questions we also have in the first 2367 02:57:10,490 --> 02:57:08,220 place it's how are Alka and Jack Maja 2368 02:57:13,190 --> 02:57:10,500 are compared how are these hydrothermal 2369 02:57:16,910 --> 02:57:13,200 vein systems related because uh our 2370 02:57:20,030 --> 02:57:16,920 contigma are like two kilometers away so 2371 02:57:23,030 --> 02:57:20,040 we wanted to compare how much are they 2372 02:57:24,950 --> 02:57:23,040 similar in terms of the geochemistry and 2373 02:57:29,769 --> 02:57:24,960 all the microbiology that we have been 2374 02:57:32,750 --> 02:57:29,779 found in so we perform this MDS analysis 2375 02:57:35,389 --> 02:57:32,760 so if you see that we have three 2376 02:57:38,330 --> 02:57:35,399 different locations Alka and jagmada are 2377 02:57:40,370 --> 02:57:38,340 the Hamilton Fields but we also have a 2378 02:57:42,349 --> 02:57:40,380 Dollar location that is called your 2379 02:57:45,290 --> 02:57:42,359 vacuum I'm sorry for the names all the 2380 02:57:48,469 --> 02:57:45,300 names are native words from the region 2381 02:57:51,889 --> 02:57:48,479 so that's how we decided Well scientists 2382 02:57:54,830 --> 02:57:51,899 have decided to to name them these both 2383 02:57:57,469 --> 02:57:54,840 are hydrothermal vein systems but all 2384 02:58:00,170 --> 02:57:57,479 the vacuum is a site between them but 2385 02:58:03,170 --> 02:58:00,180 it's a death uh hydrothermal veins site 2386 02:58:07,670 --> 02:58:03,180 so it's not active anymore so we use it 2387 02:58:10,730 --> 02:58:07,680 as an outsider to do this test so in 2388 02:58:14,690 --> 02:58:10,740 general terms you can see that they are 2389 02:58:17,630 --> 02:58:14,700 very similar okay and and jagma and here 2390 02:58:22,309 --> 02:58:17,640 is this is the outsider your vacuum that 2391 02:58:25,130 --> 02:58:22,319 it looks um not that similar to them so 2392 02:58:27,710 --> 02:58:25,140 they are sharing uh a lot of of things 2393 02:58:29,809 --> 02:58:27,720 but we are exactly we don't say we don't 2394 02:58:32,450 --> 02:58:29,819 know what if it's the geochemistry of 2395 02:58:35,090 --> 02:58:32,460 this the microbiology so 2396 02:58:36,950 --> 02:58:35,100 um we want to go further in to study the 2397 02:58:39,290 --> 02:58:36,960 microbial composition of both of them 2398 02:58:41,210 --> 02:58:39,300 and compare them and to see if they are 2399 02:58:44,090 --> 02:58:41,220 related or what are the difference 2400 02:58:44,750 --> 02:58:44,100 between them and one of the 2401 02:58:48,590 --> 02:58:44,760 um 2402 02:58:50,450 --> 02:58:48,600 a biggest surprises that we have is that 2403 02:58:52,910 --> 02:58:50,460 the microbes are related to the 2404 02:58:56,090 --> 02:58:52,920 hydrothermal fluids but between Alka and 2405 02:58:59,469 --> 02:58:56,100 jagma the well the microbes are 2406 02:59:01,929 --> 02:58:59,479 different they have we have different a 2407 02:59:06,349 --> 02:59:01,939 film composition 2408 02:59:07,929 --> 02:59:06,359 uh but the only uh film they share is 2409 02:59:10,190 --> 02:59:07,939 Thermo thermostat 2410 02:59:12,830 --> 02:59:10,200 so this is a very 2411 02:59:14,870 --> 02:59:12,840 um interesting thing to to explore that 2412 02:59:16,730 --> 02:59:14,880 we are finding different microbial 2413 02:59:18,769 --> 02:59:16,740 communities between those those are 2414 02:59:21,849 --> 02:59:18,779 thermal veins but we are they are 2415 02:59:25,730 --> 02:59:21,859 sharing one so this is telling us about 2416 02:59:28,450 --> 02:59:25,740 the thermophilic and hydrothermal flow 2417 02:59:30,830 --> 02:59:28,460 is all the ambient all the the 2418 02:59:34,309 --> 02:59:30,840 conditions extreme conditions that are 2419 02:59:35,750 --> 02:59:34,319 around and also they tell us about all 2420 02:59:38,210 --> 02:59:35,760 the um 2421 02:59:41,269 --> 02:59:38,220 your Chemistry that is happening is 2422 02:59:42,950 --> 02:59:41,279 telling us about all it's very complex I 2423 02:59:45,410 --> 02:59:42,960 think that all the metabolism that is 2424 02:59:47,990 --> 02:59:45,420 going on between these sediments around 2425 02:59:51,230 --> 02:59:48,000 Harold Hamilton events so we are trying 2426 02:59:53,530 --> 02:59:51,240 to explore furthermore about this uh 2427 02:59:55,969 --> 02:59:53,540 group the thermo togoda that they are 2428 03:00:00,410 --> 02:59:55,979 extremophiles they are adopted more than 2429 03:00:03,830 --> 03:00:00,420 50 degrees or 80 degrees Celsius so we 2430 03:00:05,269 --> 03:00:03,840 are trying to to understand if these are 2431 03:00:07,730 --> 03:00:05,279 like the same families that they are 2432 03:00:11,030 --> 03:00:07,740 sharing or not that's one of the next 2433 03:00:12,950 --> 03:00:11,040 steps for this but also the implications 2434 03:00:16,090 --> 03:00:12,960 for astrobiology in term for a 2435 03:00:19,490 --> 03:00:16,100 hypothermal veins is that we are ex 2436 03:00:21,769 --> 03:00:19,500 still exploring a lot of findings on 2437 03:00:24,050 --> 03:00:21,779 thermophilic microbial communities in 2438 03:00:26,269 --> 03:00:24,060 this hydrothermal vein systems so try to 2439 03:00:29,389 --> 03:00:26,279 understand the limits of Life on our 2440 03:00:31,190 --> 03:00:29,399 Earth as it is one of the deepest points 2441 03:00:33,830 --> 03:00:31,200 of the Pacific Ocean it is telling us a 2442 03:00:37,370 --> 03:00:33,840 lot of information about that and also 2443 03:00:39,769 --> 03:00:37,380 all another step for the investigation 2444 03:00:41,809 --> 03:00:39,779 that is going on it's applying it to the 2445 03:00:45,889 --> 03:00:41,819 icy moons with habitable habitability 2446 03:00:47,110 --> 03:00:45,899 models where we can try to add these 2447 03:00:51,170 --> 03:00:47,120 ecological 2448 03:00:54,290 --> 03:00:51,180 models and now we have data to try to 2449 03:00:56,929 --> 03:00:54,300 simulate this we have geochemistry data 2450 03:00:59,809 --> 03:00:56,939 we have microbiology data so we can try 2451 03:01:02,389 --> 03:00:59,819 to approach ecological model to the 2452 03:01:05,630 --> 03:01:02,399 isomers if someone in the isemons wants 2453 03:01:08,290 --> 03:01:05,640 to collaborate please let me know 2454 03:01:11,150 --> 03:01:08,300 um uh well the highlights of this 2455 03:01:12,710 --> 03:01:11,160 presentations to take away I want you to 2456 03:01:14,929 --> 03:01:12,720 well to 2457 03:01:16,790 --> 03:01:14,939 uh to show you some of the hydrothermal 2458 03:01:20,030 --> 03:01:16,800 veins how the hydrothermal vent system 2459 03:01:23,210 --> 03:01:20,040 looks like in pascular Basin but this is 2460 03:01:25,130 --> 03:01:23,220 the first uh insight into Jack Maja 2461 03:01:27,110 --> 03:01:25,140 ahara thermal vent field and its 2462 03:01:30,590 --> 03:01:27,120 microbiology the first time that we have 2463 03:01:32,630 --> 03:01:30,600 seen this our findings provide valuable 2464 03:01:34,849 --> 03:01:32,640 insight into the deep sea biosphere and 2465 03:01:36,830 --> 03:01:34,859 that we are learning that we there are a 2466 03:01:39,490 --> 03:01:36,840 lot of information that still need to be 2467 03:01:43,610 --> 03:01:39,500 processed and to know and to discover 2468 03:01:45,830 --> 03:01:43,620 and we have uh found a diverse range of 2469 03:01:47,929 --> 03:01:45,840 extremophiles in microbial communities 2470 03:01:50,389 --> 03:01:47,939 right now I'm just talking about the 2471 03:01:53,750 --> 03:01:50,399 thermophiles but we have methane 2472 03:01:55,969 --> 03:01:53,760 oxidizers anaerobic micro microbial 2473 03:01:58,969 --> 03:01:55,979 organisms so there are a lot of things 2474 03:02:00,889 --> 03:01:58,979 going not in the in the tab and well 2475 03:02:03,410 --> 03:02:00,899 knowing that the Pescadero Basin is the 2476 03:02:05,630 --> 03:02:03,420 deepest hydrothermal ecosystem in the 2477 03:02:07,849 --> 03:02:05,640 Pacific Ocean well it implies that we 2478 03:02:11,389 --> 03:02:07,859 are still understanding the limits of 2479 03:02:13,730 --> 03:02:11,399 life on Earth ambitions so with this I 2480 03:02:15,710 --> 03:02:13,740 want to thank you please uh if you want 2481 03:02:18,290 --> 03:02:15,720 to know a little more about the Mexican 2482 03:02:20,269 --> 03:02:18,300 astrology Society there is a link and I 2483 03:02:21,769 --> 03:02:20,279 am also from the astrobiology lab at 2484 03:02:22,920 --> 03:02:21,779 UNAM and we are happy to collaborate 2485 03:02:41,590 --> 03:02:22,930 thank you 2486 03:02:43,969 --> 03:02:41,600 um I was just curious do you find many 2487 03:02:46,070 --> 03:02:43,979 nanoprokaryotes like Nano archaea or 2488 03:02:48,650 --> 03:02:46,080 like candidate Philo radiation bacteria 2489 03:02:50,150 --> 03:02:48,660 and or do just filter them out in your 2490 03:02:52,070 --> 03:02:50,160 analyzes somehow or like are there any 2491 03:02:55,190 --> 03:02:52,080 interesting patterns 2492 03:02:57,530 --> 03:02:55,200 well Ryan well we're finding uh also 2493 03:02:59,750 --> 03:02:57,540 Archaea and bacteria well that's like 2494 03:03:02,210 --> 03:02:59,760 the further that we have like now there 2495 03:03:03,889 --> 03:03:02,220 is a lot still no information to to show 2496 03:03:05,269 --> 03:03:03,899 up but there is there's a lot of things 2497 03:03:07,550 --> 03:03:05,279 going on 2498 03:03:09,230 --> 03:03:07,560 yeah I just remember like looking 2499 03:03:11,570 --> 03:03:09,240 through various papers is there a lot of 2500 03:03:13,969 --> 03:03:11,580 them a lot of those like Nano sized 2501 03:03:16,730 --> 03:03:13,979 Clays present in the hydrogen events 2502 03:03:19,269 --> 03:03:16,740 like Nano archiora or yeah like nanarkio 2503 03:03:25,429 --> 03:03:19,279 or yeah 2504 03:03:31,910 --> 03:03:29,330 yes sorry uh just kind of curious I I'm 2505 03:03:35,150 --> 03:03:31,920 um so I'm a physics kind of background 2506 03:03:36,349 --> 03:03:35,160 person of mrsd and 2507 03:03:39,349 --> 03:03:36,359 I was wondering about temperature 2508 03:03:40,790 --> 03:03:39,359 management so like you know above above 2509 03:03:42,349 --> 03:03:40,800 certain temperatures like you're gonna 2510 03:03:44,090 --> 03:03:42,359 get denatured proteins and stuff like 2511 03:03:46,910 --> 03:03:44,100 that and I was wondering if there's 2512 03:03:49,250 --> 03:03:46,920 extremophiles that do like that cool 2513 03:03:51,290 --> 03:03:49,260 themselves somehow or any anything like 2514 03:03:54,590 --> 03:03:51,300 that sorry 2515 03:03:57,410 --> 03:03:54,600 yes uh actually well right now I'm here 2516 03:04:00,710 --> 03:03:57,420 I'm talking again as uh with 2517 03:04:02,510 --> 03:04:00,720 thermophiles but actually here in the 2518 03:04:04,550 --> 03:04:02,520 hierothermal veins well not the 2519 03:04:06,170 --> 03:04:04,560 hydrothermal vents around thermal veins 2520 03:04:08,750 --> 03:04:06,180 all these sediments there are different 2521 03:04:10,790 --> 03:04:08,760 changes in temperature so right now I am 2522 03:04:14,570 --> 03:04:10,800 talking about the highest ones that we 2523 03:04:17,150 --> 03:04:14,580 have a measure but if you go further the 2524 03:04:21,290 --> 03:04:17,160 hydrothermal bands it drops to 2 degrees 2525 03:04:23,330 --> 03:04:21,300 Centigrades so we are studying well it's 2526 03:04:25,070 --> 03:04:23,340 able to study different microbial 2527 03:04:27,230 --> 03:04:25,080 communities adapted to high temperatures 2528 03:04:31,190 --> 03:04:27,240 but also to call call these places 2529 03:04:31,200 --> 03:04:40,190 any other questions for a minute 2530 03:04:45,110 --> 03:04:42,590 hey really awesome talk this is really 2531 03:04:46,429 --> 03:04:45,120 cool I worked with hydrothem events as 2532 03:04:48,170 --> 03:04:46,439 an undergrad so this is like really 2533 03:04:50,330 --> 03:04:48,180 nostalgic for me 2534 03:04:52,610 --> 03:04:50,340 um I'm curious if anyone in your group 2535 03:04:54,050 --> 03:04:52,620 or anyone part of the the cruise is 2536 03:04:56,210 --> 03:04:54,060 doing it and 2537 03:04:58,849 --> 03:04:56,220 Karen Lloyd wouldn't wouldn't like this 2538 03:05:02,630 --> 03:04:58,859 but is doing any culturing from these 2539 03:05:04,730 --> 03:05:02,640 environments yes like specifically I'm 2540 03:05:06,530 --> 03:05:04,740 thinking at high pressure because these 2541 03:05:07,670 --> 03:05:06,540 are some of the like deeper vents in the 2542 03:05:09,290 --> 03:05:07,680 Pacific or the deepest vents in the 2543 03:05:11,630 --> 03:05:09,300 Pacific I think you said and so I'm just 2544 03:05:14,690 --> 03:05:11,640 curious if anyone's doing culturing and 2545 03:05:19,370 --> 03:05:14,700 if they're including pressure in that 2546 03:05:21,469 --> 03:05:19,380 Yes actually one of the uh here in one 2547 03:05:25,309 --> 03:05:21,479 of the collaborations that we have is in 2548 03:05:27,170 --> 03:05:25,319 Caltech in Victoria orphan's lab yes uh 2549 03:05:30,010 --> 03:05:27,180 the group are making some cultural 2550 03:05:32,690 --> 03:05:30,020 experiments with some of the different 2551 03:05:35,389 --> 03:05:32,700 sediment cores in different sites so 2552 03:05:37,490 --> 03:05:35,399 they are trying to to do that and they 2553 03:05:40,190 --> 03:05:37,500 have also published one paper about 2554 03:05:42,650 --> 03:05:40,200 culture in archaea I think so they are 2555 03:05:44,870 --> 03:05:42,660 they are doing it but of course the 2556 03:05:46,910 --> 03:05:44,880 challenging things about depression so 2557 03:05:50,090 --> 03:05:46,920 they have like this tank 2558 03:05:51,710 --> 03:05:50,100 to try to approach that yes they are 2559 03:05:53,150 --> 03:05:51,720 trying to do cultural techniques for 2560 03:05:56,809 --> 03:05:53,160 this 2561 03:05:56,819 --> 03:06:10,849 any questions here 2562 03:06:14,330 --> 03:06:13,309 I thank you for the talk 2563 03:06:18,710 --> 03:06:14,340 um 2564 03:06:21,050 --> 03:06:18,720 I have a very trivial question uh we've 2565 03:06:23,090 --> 03:06:21,060 been having issues with sediment samples 2566 03:06:26,450 --> 03:06:23,100 in our lab 2567 03:06:28,969 --> 03:06:26,460 um freaking out how not to contaminate 2568 03:06:31,730 --> 03:06:28,979 them or not being sure if they are 2569 03:06:34,849 --> 03:06:31,740 contaminated when we are taking the 2570 03:06:36,889 --> 03:06:34,859 samples I wonder how you control control 2571 03:06:40,849 --> 03:06:36,899 for that 2572 03:06:43,670 --> 03:06:40,859 yeah that's a good question so when we 2573 03:06:45,769 --> 03:06:43,680 are working on uh on the ship 2574 03:06:47,510 --> 03:06:45,779 um back in the lab there is a lot of 2575 03:06:51,650 --> 03:06:47,520 possibilities that it got contaminated 2576 03:06:54,469 --> 03:06:51,660 we will try to be as quick as possible 2577 03:06:57,830 --> 03:06:54,479 and in clean spaces but we actually 2578 03:06:59,389 --> 03:06:57,840 where we are working with salmon course 2579 03:07:01,910 --> 03:06:59,399 it's moth 2580 03:07:04,309 --> 03:07:01,920 so it gets really moved all around we 2581 03:07:07,010 --> 03:07:04,319 try to clean but we just try to be as 2582 03:07:10,670 --> 03:07:07,020 quick as possible one of the things that 2583 03:07:13,670 --> 03:07:10,680 we rely on is a bioinformatic analysis 2584 03:07:14,469 --> 03:07:13,680 so in the informatic analysis when we 2585 03:07:17,090 --> 03:07:14,479 are 2586 03:07:19,910 --> 03:07:17,100 processing all the 16s data the 2587 03:07:23,870 --> 03:07:19,920 sequences we are filtering them so we 2588 03:07:26,570 --> 03:07:23,880 have like uh we process we have also for 2589 03:07:29,809 --> 03:07:26,580 the 16s or the DNA extractions on blanks 2590 03:07:33,650 --> 03:07:29,819 and some control samples so we tried 2591 03:07:36,889 --> 03:07:33,660 like if there is a sequence uh in the 2592 03:07:39,110 --> 03:07:36,899 blank on the control we delete them so 2593 03:07:41,090 --> 03:07:39,120 we try to filter and to make the the 2594 03:07:43,910 --> 03:07:41,100 cleanest sequence possible as possible 2595 03:07:45,889 --> 03:07:43,920 but yeah of course there is some 2596 03:07:47,570 --> 03:07:45,899 contamination and we also like sometimes 2597 03:07:49,969 --> 03:07:47,580 we see like oh that's that's not from 2598 03:07:52,309 --> 03:07:49,979 the deep sea but we try to see the the 2599 03:07:54,830 --> 03:07:52,319 sequences and try to clean them that's 2600 03:07:54,840 --> 03:07:58,910 any last questions 2601 03:07:58,920 --> 03:08:08,510 okay thank you very much thank you 2602 03:08:13,429 --> 03:08:11,269 okay so lunch is served in Surfside and 2603 03:08:23,310 --> 03:08:13,439 then we'll be back for the short talk 2604 03:09:09,130 --> 03:08:42,920 [Music] 2605 03:09:09,140 --> 03:09:15,350 thank you 2606 03:09:25,660 --> 03:09:23,349 [Music] 2607 03:09:41,130 --> 03:09:25,670 thank you 2608 03:09:52,040 --> 03:09:49,929 [Music] 2609 03:10:07,990 --> 03:09:52,050 thank you 2610 03:10:08,000 --> 03:10:25,389 [Music] 2611 03:10:30,950 --> 03:10:26,710 thank you 2612 03:10:59,140 --> 03:10:33,930 foreign 2613 03:10:59,150 --> 03:11:03,410 [Music] 2614 03:11:25,840 --> 03:11:05,270 foreign 2615 03:12:35,290 --> 03:11:51,770 [Music] 2616 03:12:35,300 --> 03:12:42,930 thank you 2617 03:13:15,010 --> 03:13:09,640 [Music] 2618 03:13:31,780 --> 03:13:15,020 thank you 2619 03:13:45,570 --> 03:13:43,849 [Music] 2620 03:13:54,800 --> 03:13:45,580 thank you 2621 03:15:33,950 --> 03:14:16,170 [Music] 2622 03:15:33,960 --> 03:15:38,670 foreign 2623 03:16:20,510 --> 03:15:46,040 [Music] 2624 03:16:20,520 --> 03:16:24,610 thank you 2625 03:16:24,620 --> 03:16:47,750 [Music] 2626 03:17:19,970 --> 03:16:49,500 foreign 2627 03:17:19,980 --> 03:17:29,510 [Music] 2628 03:17:29,520 --> 03:17:36,690 thank you 2629 03:18:00,230 --> 03:17:52,430 [Music] 2630 03:18:00,240 --> 03:18:05,760 foreign 2631 03:18:41,889 --> 03:18:18,090 [Music] 2632 03:18:50,050 --> 03:18:43,470 thank you 2633 03:19:11,990 --> 03:18:59,210 [Music] 2634 03:19:30,420 --> 03:19:13,720 foreign 2635 03:19:30,430 --> 03:19:43,130 [Music] 2636 03:19:43,140 --> 03:19:50,040 foreign 2637 03:20:13,370 --> 03:20:07,320 [Music] 2638 03:20:13,380 --> 03:20:24,020 thank you 2639 03:20:35,110 --> 03:20:30,220 [Music] 2640 03:20:35,120 --> 03:20:39,390 thank you 2641 03:21:47,170 --> 03:20:48,540 [Music] 2642 03:21:55,320 --> 03:21:50,130 thank you 2643 03:22:16,190 --> 03:22:02,180 [Music] 2644 03:22:36,800 --> 03:22:16,200 foreign 2645 03:22:36,810 --> 03:22:42,230 [Music] 2646 03:22:53,850 --> 03:22:43,340 thank you 2647 03:23:38,090 --> 03:22:56,210 [Music] 2648 03:23:38,100 --> 03:23:41,830 foreign 2649 03:24:49,140 --> 03:23:52,050 [Music] 2650 03:25:06,590 --> 03:24:49,150 foreign 2651 03:25:19,940 --> 03:25:15,760 [Music] 2652 03:25:44,910 --> 03:25:19,950 foreign 2653 03:26:11,410 --> 03:26:05,240 [Music] 2654 03:26:11,420 --> 03:26:14,580 thank you 2655 03:27:15,410 --> 03:26:26,020 [Music] 2656 03:27:21,170 --> 03:27:15,420 thank you 2657 03:27:55,660 --> 03:27:35,530 [Music] 2658 03:28:04,020 --> 03:27:55,670 foreign 2659 03:28:32,230 --> 03:28:17,030 [Music] 2660 03:28:44,440 --> 03:28:32,240 thank you 2661 03:29:03,710 --> 03:28:52,970 [Music] 2662 03:29:07,190 --> 03:29:03,720 thank you 2663 03:29:38,469 --> 03:29:16,660 [Music] 2664 03:29:38,479 --> 03:29:46,510 thank you 2665 03:30:14,450 --> 03:30:10,430 [Music] 2666 03:30:14,460 --> 03:30:17,300 foreign 2667 03:30:48,240 --> 03:30:25,480 [Music] 2668 03:31:14,860 --> 03:30:48,250 foreign 2669 03:31:28,670 --> 03:31:26,120 [Music] 2670 03:31:31,849 --> 03:31:28,680 thank you 2671 03:32:07,370 --> 03:31:31,859 [Music] 2672 03:32:39,840 --> 03:32:10,010 thank you 2673 03:33:50,990 --> 03:32:42,650 [Music] 2674 03:34:28,870 --> 03:33:56,030 foreign 2675 03:35:08,090 --> 03:34:54,610 [Music] 2676 03:35:08,100 --> 03:35:12,010 foreign 2677 03:36:22,969 --> 03:35:37,010 [Music] 2678 03:36:22,979 --> 03:36:57,010 foreign 2679 03:37:39,830 --> 03:37:08,870 [Music] 2680 03:37:39,840 --> 03:38:08,010 foreign 2681 03:38:47,690 --> 03:38:17,010 [Music] 2682 03:38:47,700 --> 03:38:52,360 foreign 2683 03:39:34,730 --> 03:39:14,380 [Music] 2684 03:40:04,450 --> 03:39:34,740 foreign 2685 03:40:04,460 --> 03:40:07,870 thank you 2686 03:40:07,880 --> 03:40:29,809 [Music] 2687 03:41:08,750 --> 03:40:31,940 quickly 2688 03:41:08,760 --> 03:41:18,320 foreign 2689 03:41:18,330 --> 03:41:47,510 [Music] 2690 03:41:59,900 --> 03:41:47,890 thank you 2691 03:42:23,450 --> 03:42:11,170 [Music] 2692 03:42:52,760 --> 03:42:24,420 foreign 2693 03:42:52,770 --> 03:43:07,910 [Music] 2694 03:43:07,920 --> 03:43:10,370 thank you 2695 03:43:43,540 --> 03:43:21,620 [Music] 2696 03:44:10,309 --> 03:43:43,550 thank you 2697 03:44:10,319 --> 03:44:13,820 foreign 2698 03:44:47,210 --> 03:44:32,090 [Music] 2699 03:44:57,240 --> 03:44:47,220 foreign 2700 03:45:20,090 --> 03:45:04,840 [Music] 2701 03:45:20,100 --> 03:45:24,270 foreign 2702 03:45:53,990 --> 03:45:31,380 [Music] 2703 03:45:54,000 --> 03:45:57,670 foreign 2704 03:46:44,090 --> 03:46:13,490 [Music] 2705 03:47:15,020 --> 03:46:47,060 foreign 2706 03:48:16,870 --> 03:47:27,790 [Music] 2707 03:48:24,450 --> 03:48:19,010 thank you 2708 03:49:30,889 --> 03:48:55,580 [Music] 2709 03:49:48,020 --> 03:49:32,380 foreign 2710 03:50:37,510 --> 03:50:00,050 [Music] 2711 03:50:37,520 --> 03:50:44,450 thank you 2712 03:50:55,450 --> 03:50:46,260 foreign 2713 03:51:49,010 --> 03:51:14,070 [Music] 2714 03:52:06,020 --> 03:51:50,850 foreign 2715 03:53:05,510 --> 03:52:31,920 [Music] 2716 03:53:08,610 --> 03:53:07,429 thank you 2717 03:53:13,910 --> 03:53:08,620 foreign 2718 03:54:03,229 --> 03:53:41,630 [Music] 2719 03:54:19,450 --> 03:54:03,960 foreign 2720 03:54:19,460 --> 03:54:24,760 excuse me 2721 03:58:41,780 --> 03:54:31,650 [Music] 2722 03:58:49,969 --> 03:58:48,410 [Applause] 2723 03:58:51,349 --> 03:58:49,979 all right hello everyone how's it going 2724 03:58:53,450 --> 03:58:51,359 my name's Sean I'm from the University 2725 03:58:54,830 --> 03:58:53,460 of Maryland Baltimore County and today 2726 03:58:56,570 --> 03:58:54,840 we're going to be looking at xenoamino 2727 03:58:58,910 --> 03:58:56,580 acids a look into biochemistry as we 2728 03:59:00,229 --> 03:58:58,920 don't know it so I'm going to fly 2729 03:59:01,790 --> 03:59:00,239 through a lot of this because it's only 2730 03:59:03,530 --> 03:59:01,800 a six minute talk but please come for 2731 03:59:05,570 --> 03:59:03,540 feel free to come find me at my poster 2732 03:59:08,210 --> 03:59:05,580 outside afterwards so my project 2733 03:59:10,910 --> 03:59:08,220 attempts to merge Theory with experiment 2734 03:59:12,769 --> 03:59:10,920 in order to test if a alternative amino 2735 03:59:14,750 --> 03:59:12,779 acid set is capable of building protein 2736 03:59:16,250 --> 03:59:14,760 structure now to do this we need to 2737 03:59:18,889 --> 03:59:16,260 select a candidate alphabet from 2738 03:59:21,229 --> 03:59:18,899 plausible Alternatives and from there 2739 03:59:23,889 --> 03:59:21,239 use our collaborators over at the 2740 03:59:26,990 --> 03:59:23,899 Charles University in Prague to build 2741 03:59:28,550 --> 03:59:27,000 oligopeptides now I'm going to take a 2742 03:59:30,229 --> 03:59:28,560 step back here and go over some very 2743 03:59:33,349 --> 03:59:30,239 quick background 2744 03:59:35,450 --> 03:59:33,359 um so all life on Earth since Lucas use 2745 03:59:37,550 --> 03:59:35,460 the same set of 20 Alpha amino acids to 2746 03:59:39,110 --> 03:59:37,560 construct metabolism now multiple 2747 03:59:40,790 --> 03:59:39,120 disciplines agree that there were far 2748 03:59:43,189 --> 03:59:40,800 more than 20 available for early 2749 03:59:45,410 --> 03:59:43,199 evolution in the origins of life 2750 03:59:46,389 --> 03:59:45,420 and over the last decade or so there's 2751 03:59:48,650 --> 03:59:46,399 been 2752 03:59:51,349 --> 03:59:48,660 theoretical work that identifies as 2753 03:59:53,870 --> 03:59:51,359 simple but statistical profile that 2754 03:59:56,330 --> 03:59:53,880 distinguishes life's amino acids from 2755 03:59:58,910 --> 03:59:56,340 Alternatives and that is that the 20 2756 04:00:01,729 --> 03:59:58,920 amino acids used by life exhibit a 2757 04:00:03,950 --> 04:00:01,739 non-random coverage of size and 2758 04:00:06,110 --> 04:00:03,960 hydrophobicity when we Define coverage 2759 04:00:08,750 --> 04:00:06,120 as the range of values in a set and with 2760 04:00:11,090 --> 04:00:08,760 how and how they how evenly they 2761 04:00:12,889 --> 04:00:11,100 distribute across that range 2762 04:00:14,330 --> 04:00:12,899 so what do I mean by that exactly I want 2763 04:00:16,910 --> 04:00:14,340 you to consider a set of five amino 2764 04:00:20,030 --> 04:00:16,920 acids and pick any physical chemical 2765 04:00:22,969 --> 04:00:20,040 descriptor this could be size this could 2766 04:00:25,130 --> 04:00:22,979 be volume I'm sorry uh log P this could 2767 04:00:27,290 --> 04:00:25,140 be charge and you're going to measure 2768 04:00:30,110 --> 04:00:27,300 them rank order them and plot them on 2769 04:00:32,929 --> 04:00:30,120 that axis from here what we can do is we 2770 04:00:35,689 --> 04:00:32,939 can get the intervals between each amino 2771 04:00:37,610 --> 04:00:35,699 acid and this ties into our our idea of 2772 04:00:39,469 --> 04:00:37,620 coverage which breaks down into two 2773 04:00:42,110 --> 04:00:39,479 components which is range and evenness 2774 04:00:44,630 --> 04:00:42,120 so range is simply just the sum of these 2775 04:00:46,849 --> 04:00:44,640 intervals between each amino acid and 2776 04:00:49,309 --> 04:00:46,859 evenness is the sample variance of these 2777 04:00:51,950 --> 04:00:49,319 intervals now this ties back into what I 2778 04:00:55,490 --> 04:00:51,960 said the coded 20 amino acids are 2779 04:00:58,330 --> 04:00:55,500 statistically non-random in one in about 2780 04:01:01,309 --> 04:00:58,340 two and a half million alternative 2781 04:01:05,389 --> 04:01:01,319 alphabets would have the same or better 2782 04:01:08,630 --> 04:01:05,399 coverage in size and hydrophobicity 2783 04:01:11,450 --> 04:01:08,640 now why exactly are we looking at range 2784 04:01:13,910 --> 04:01:11,460 in evenness well range allows for a 2785 04:01:17,210 --> 04:01:13,920 broader diversity of structures and 2786 04:01:18,769 --> 04:01:17,220 functions and evenness allows for the 2787 04:01:20,450 --> 04:01:18,779 best approximation of any desired 2788 04:01:23,269 --> 04:01:20,460 physical chemistry so I like to think of 2789 04:01:25,790 --> 04:01:23,279 it as trying to recreate a black and 2790 04:01:28,490 --> 04:01:25,800 white painting using a defined set of 2791 04:01:31,309 --> 04:01:28,500 tiles and you need to pick which colors 2792 04:01:34,010 --> 04:01:31,319 you want to use to try and get that 2793 04:01:35,929 --> 04:01:34,020 painting as close as possible now range 2794 04:01:38,570 --> 04:01:35,939 is effectively the difference between 2795 04:01:40,849 --> 04:01:38,580 having black and white tiles versus just 2796 04:01:42,290 --> 04:01:40,859 different Shades of Gray and evenness is 2797 04:01:44,570 --> 04:01:42,300 among the black and white tiles having 2798 04:01:45,650 --> 04:01:44,580 an even distribution going from black to 2799 04:01:48,769 --> 04:01:45,660 white 2800 04:01:50,929 --> 04:01:48,779 now why exactly are we looking at log p 2801 04:01:53,090 --> 04:01:50,939 and volume log p is just a measure of 2802 04:01:55,729 --> 04:01:53,100 hydrophobicity and hydrophobic collapse 2803 04:01:57,229 --> 04:01:55,739 is crucial for protein folding and for 2804 04:02:00,170 --> 04:01:57,239 volume volume determines the physical 2805 04:02:01,610 --> 04:02:00,180 space that allows for protein folding 2806 04:02:03,590 --> 04:02:01,620 so now that we have this idea of 2807 04:02:06,410 --> 04:02:03,600 coverage in our mind I would like to 2808 04:02:07,490 --> 04:02:06,420 very quickly go over our workflow I'm 2809 04:02:10,729 --> 04:02:07,500 going to skip essentially everything 2810 04:02:12,229 --> 04:02:10,739 except that top right corner where all 2811 04:02:14,150 --> 04:02:12,239 we're doing is we have a heuristic 2812 04:02:16,309 --> 04:02:14,160 search protocol that searches a library 2813 04:02:18,650 --> 04:02:16,319 of purchasable amino acids 2814 04:02:20,929 --> 04:02:18,660 and from there we are in a constant 2815 04:02:22,849 --> 04:02:20,939 feedback loop with our empiricist 2816 04:02:25,910 --> 04:02:22,859 collaborators in attempting to 2817 04:02:28,670 --> 04:02:25,920 eventually get a candidate alphabet 2818 04:02:30,110 --> 04:02:28,680 now I'm sure you are all dying to see 2819 04:02:31,550 --> 04:02:30,120 what one of these alphabets look like 2820 04:02:33,830 --> 04:02:31,560 right 2821 04:02:38,090 --> 04:02:33,840 so here we go uh this is our current 2822 04:02:40,250 --> 04:02:38,100 alphabet now big emphasis on current 2823 04:02:41,689 --> 04:02:40,260 um because of that iterative feedback 2824 04:02:43,070 --> 04:02:41,699 loop this is definitely subject to 2825 04:02:45,769 --> 04:02:43,080 change and probably will change before 2826 04:02:48,889 --> 04:02:45,779 we start constructing oligopeptides from 2827 04:02:52,429 --> 04:02:48,899 a set but here is our first set um this 2828 04:02:55,610 --> 04:02:52,439 is simply just one example of around 10 2829 04:02:57,650 --> 04:02:55,620 to the 14 possible High coverage sets 2830 04:03:00,469 --> 04:02:57,660 that we could pick from so there are a 2831 04:03:04,610 --> 04:03:00,479 lot of variations that we can change and 2832 04:03:07,010 --> 04:03:04,620 play with with the empiricists now again 2833 04:03:08,870 --> 04:03:07,020 the goal here is to synthesize these 2834 04:03:10,729 --> 04:03:08,880 oligopeptides from a completely 2835 04:03:13,610 --> 04:03:10,739 non-canonical set 2836 04:03:15,469 --> 04:03:13,620 and that's hopefully what we'll be doing 2837 04:03:19,189 --> 04:03:15,479 in a few weeks 2838 04:03:22,570 --> 04:03:19,199 now I would like to very quickly end on 2839 04:03:25,189 --> 04:03:22,580 a deeper note of who cares 2840 04:03:28,309 --> 04:03:25,199 uh why would an advanced science to 2841 04:03:30,889 --> 04:03:28,319 design an alternative amino acid set and 2842 04:03:33,889 --> 04:03:30,899 I would like to kind of bring that 2843 04:03:36,110 --> 04:03:33,899 question to this idea of is there such a 2844 04:03:39,530 --> 04:03:36,120 thing as a good or bad amino acid 2845 04:03:40,969 --> 04:03:39,540 alphabet now before the empiricists and 2846 04:03:42,530 --> 04:03:40,979 the crowd jump out of their chairs and 2847 04:03:44,929 --> 04:03:42,540 strangle me 2848 04:03:47,510 --> 04:03:44,939 um yes the empiricists are saying of 2849 04:03:49,670 --> 04:03:47,520 course there are bad amino acid sets the 2850 04:03:51,290 --> 04:03:49,680 20 are very good at what they do but 2851 04:03:53,269 --> 04:03:51,300 theorists are pushing back a little bit 2852 04:03:56,689 --> 04:03:53,279 and saying well you know Evolution can 2853 04:03:58,969 --> 04:03:56,699 find any needle in any Haystack so I 2854 04:04:01,130 --> 04:03:58,979 would like to believe that the the truth 2855 04:04:03,170 --> 04:04:01,140 lies somewhere in between but what we're 2856 04:04:06,410 --> 04:04:03,180 really trying to do here is begin to 2857 04:04:09,050 --> 04:04:06,420 characterize good versus bad using an 2858 04:04:11,510 --> 04:04:09,060 adaptation of 1980s behavioral thinking 2859 04:04:15,229 --> 04:04:11,520 so optimality theory for life's amino 2860 04:04:17,330 --> 04:04:15,239 acids now I'd like to conclude just by 2861 04:04:20,889 --> 04:04:17,340 thanking our sponsors or I'm sorry our 2862 04:04:23,450 --> 04:04:20,899 sponsors our funders 2863 04:04:25,910 --> 04:04:23,460 and our collaborators over at the 2864 04:04:27,590 --> 04:04:25,920 Charles University in Prague and if you 2865 04:04:29,330 --> 04:04:27,600 would like to talk to me about this in 2866 04:04:31,670 --> 04:04:29,340 much much greater depth please find me 2867 04:04:37,340 --> 04:04:31,680 at poster 24 which is outside thank you 2868 04:04:37,350 --> 04:04:40,910 [Applause] 2869 04:04:48,710 --> 04:04:43,849 our next speakers Peter Winslow from the 2870 04:04:54,530 --> 04:04:52,429 so um my talk is in a similar vein 2871 04:04:58,910 --> 04:04:54,540 um I'm going to try to convince you all 2872 04:05:01,070 --> 04:04:58,920 that I can study the first proteins 2873 04:05:02,510 --> 04:05:01,080 um and how they might have functioned so 2874 04:05:05,630 --> 04:05:02,520 before I get to that I would like to 2875 04:05:07,550 --> 04:05:05,640 acknowledge Matilda Newton who came out 2876 04:05:10,849 --> 04:05:07,560 of my lab they did a lot of the work 2877 04:05:13,729 --> 04:05:10,859 that this is all based off of so 2878 04:05:15,650 --> 04:05:13,739 um to start off our lab is interested 2879 04:05:17,570 --> 04:05:15,660 like I said origin of the first 2880 04:05:20,330 --> 04:05:17,580 functional proteins so it's pretty well 2881 04:05:23,450 --> 04:05:20,340 established by you know chemistry that 2882 04:05:26,630 --> 04:05:23,460 you can get abiotic synthesis of amino 2883 04:05:29,150 --> 04:05:26,640 acids right so Miller experiment we find 2884 04:05:30,650 --> 04:05:29,160 them on meteorites this sort of subset 2885 04:05:34,250 --> 04:05:30,660 of the 20 amino acids we use today 2886 04:05:36,469 --> 04:05:34,260 around you know half 10 to 12. and then 2887 04:05:38,030 --> 04:05:36,479 at some point these polymerize and you 2888 04:05:40,490 --> 04:05:38,040 have polypeptides but they're not really 2889 04:05:42,050 --> 04:05:40,500 functional and then 2890 04:05:44,689 --> 04:05:42,060 um something happens and now we have 2891 04:05:46,849 --> 04:05:44,699 proteins and then you know billions of 2892 04:05:48,889 --> 04:05:46,859 years of evolution and we have modern 20 2893 04:05:51,590 --> 04:05:48,899 Amino acid-based protein what I'm 2894 04:05:53,570 --> 04:05:51,600 focused on is this this period of time 2895 04:05:56,570 --> 04:05:53,580 where we go from random chains of 2896 04:05:59,030 --> 04:05:56,580 polypeptides to functional proteins that 2897 04:06:02,269 --> 04:05:59,040 are conferring some sort of Advantage 2898 04:06:04,189 --> 04:06:02,279 right but when we look at these the the 2899 04:06:06,050 --> 04:06:04,199 key thing is they don't have all 20 2900 04:06:08,210 --> 04:06:06,060 amino acids they have 2901 04:06:10,490 --> 04:06:08,220 some sort of subset of these primordial 2902 04:06:12,349 --> 04:06:10,500 amino acids so what what are primordial 2903 04:06:14,870 --> 04:06:12,359 amino acids well 2904 04:06:17,389 --> 04:06:14,880 um we're focusing on the 20 amino acids 2905 04:06:20,510 --> 04:06:17,399 that biology uses today no Xeno amino 2906 04:06:23,750 --> 04:06:20,520 acids unfortunately but we sort of we 2907 04:06:26,689 --> 04:06:23,760 used a consensus of the addition of 2908 04:06:27,950 --> 04:06:26,699 different amino acids using more than 60 2909 04:06:29,870 --> 04:06:27,960 different theories from many different 2910 04:06:31,969 --> 04:06:29,880 fields mathematics chemistry biology 2911 04:06:33,590 --> 04:06:31,979 biochemistry 2912 04:06:36,349 --> 04:06:33,600 um and then we arbitrarily create 2913 04:06:39,050 --> 04:06:36,359 different alphabets sort of to create 2914 04:06:43,790 --> 04:06:39,060 time shots like snapshots of the this 2915 04:06:46,010 --> 04:06:43,800 timeline so 2016 9 and 5. and with this 2916 04:06:49,130 --> 04:06:46,020 we think we can answer a few big 2917 04:06:51,710 --> 04:06:49,140 questions so can you get biological 2918 04:06:54,110 --> 04:06:51,720 function from primordial alphabets 2919 04:06:56,570 --> 04:06:54,120 what is the minimum alphabet needed for 2920 04:06:59,150 --> 04:06:56,580 these proteins to function and if they 2921 04:07:02,090 --> 04:06:59,160 do function how are they similar to 2922 04:07:03,349 --> 04:07:02,100 Modern proteins so to investigate these 2923 04:07:04,929 --> 04:07:03,359 questions we 2924 04:07:07,849 --> 04:07:04,939 created 2925 04:07:10,130 --> 04:07:07,859 with these four alphabets large 2926 04:07:12,830 --> 04:07:10,140 libraries of completely random adiabino 2927 04:07:16,010 --> 04:07:12,840 acid long proteins so 10 trillion random 2928 04:07:17,570 --> 04:07:16,020 proteins in each different library and 2929 04:07:20,510 --> 04:07:17,580 we use a screen for a really simple 2930 04:07:22,429 --> 04:07:20,520 function ATP binding it's pretty you 2931 04:07:24,769 --> 04:07:22,439 know ubiquitous throughout all life 2932 04:07:28,630 --> 04:07:24,779 and we kind of just saw what we could 2933 04:07:31,189 --> 04:07:28,640 see and believe it or not every 2934 04:07:32,870 --> 04:07:31,199 Library actually yielded functional 2935 04:07:35,330 --> 04:07:32,880 proteins which we were really surprised 2936 04:07:37,910 --> 04:07:35,340 about we kind of aimed for the 20 amino 2937 04:07:39,410 --> 04:07:37,920 acid alphabet library to be sort of 2938 04:07:41,809 --> 04:07:39,420 positive control right because it's 2939 04:07:43,790 --> 04:07:41,819 modern we know those work and we sort of 2940 04:07:45,229 --> 04:07:43,800 aim for the five to be a negative 2941 04:07:48,530 --> 04:07:45,239 control because we really did not expect 2942 04:07:50,330 --> 04:07:48,540 those to bind ATP but they all do and 2943 04:07:53,630 --> 04:07:50,340 actually the five performs just as well 2944 04:07:57,290 --> 04:07:53,640 as the 20. so now we know 2945 04:08:00,010 --> 04:07:57,300 reduced amino acid proteins they 2946 04:08:02,689 --> 04:08:00,020 function but we don't know how 2947 04:08:04,729 --> 04:08:02,699 especially these really reduced ones 2948 04:08:09,229 --> 04:08:04,739 they're lacking a lot of key residues 2949 04:08:10,490 --> 04:08:09,239 that extend ATP binders use so that's 2950 04:08:12,429 --> 04:08:10,500 what I've been working on the last year 2951 04:08:15,710 --> 04:08:12,439 is trying to figure out how these work 2952 04:08:16,910 --> 04:08:15,720 and so I've been trying to characterize 2953 04:08:18,889 --> 04:08:16,920 them structurally through x-ray 2954 04:08:20,630 --> 04:08:18,899 crystallography so if you don't know 2955 04:08:22,910 --> 04:08:20,640 about extrater photography it's just you 2956 04:08:25,130 --> 04:08:22,920 crystallized protein you collect 2957 04:08:27,050 --> 04:08:25,140 diffraction data and you can extrapolate 2958 04:08:30,530 --> 04:08:27,060 that to get electron density and then 2959 04:08:32,689 --> 04:08:30,540 model that into a protein structure so 2960 04:08:34,189 --> 04:08:32,699 with this we really want to look at from 2961 04:08:35,389 --> 04:08:34,199 some of these best binders that we've 2962 04:08:37,550 --> 04:08:35,399 found 2963 04:08:40,130 --> 04:08:37,560 what is The Binding mechanism 2964 04:08:42,710 --> 04:08:40,140 how similar how different it is it to 2965 04:08:45,110 --> 04:08:42,720 Modern proteins because if it's similar 2966 04:08:47,030 --> 04:08:45,120 that's really exciting maybe this was 2967 04:08:49,610 --> 04:08:47,040 sort of always bound to happen and if 2968 04:08:51,769 --> 04:08:49,620 it's different maybe that means it's 2969 04:08:53,210 --> 04:08:51,779 sort of Frozen accident and we can see a 2970 04:08:55,910 --> 04:08:53,220 sort of sample from a completely 2971 04:08:57,710 --> 04:08:55,920 different sequence space and also how 2972 04:08:59,570 --> 04:08:57,720 dependent on alphabet complexity is 2973 04:09:01,010 --> 04:08:59,580 protein functionality which kind of goes 2974 04:09:02,689 --> 04:09:01,020 back to the last talk 2975 04:09:04,090 --> 04:09:02,699 so with that um I'd just like to thank 2976 04:09:07,250 --> 04:09:04,100 everyone in my lab 2977 04:09:08,809 --> 04:09:07,260 and our collaborators from the 2978 04:09:11,030 --> 04:09:08,819 University of Minnesota but also from 2979 04:09:12,830 --> 04:09:11,040 UCLA specifically Irene chin and Celia 2980 04:09:14,540 --> 04:09:12,840 Blanco so if you have any questions see 2981 04:09:23,090 --> 04:09:14,550 me at poster16. 2982 04:09:26,210 --> 04:09:23,100 [Applause] 2983 04:09:33,349 --> 04:09:26,220 our next speaker is Rudy gandalikar from 2984 04:09:37,250 --> 04:09:36,110 hello everyone I'm riddhi I'm a graduate 2985 04:09:38,710 --> 04:09:37,260 student at the Earth Life Science 2986 04:09:41,030 --> 04:09:38,720 Institute 2987 04:09:43,670 --> 04:09:41,040 in our study we have tried to understand 2988 04:09:46,729 --> 04:09:43,680 scaling of protein function across the 2989 04:09:49,250 --> 04:09:46,739 tree of life and the mechanisms that 2990 04:09:52,550 --> 04:09:49,260 might have led to the species diversity 2991 04:09:54,830 --> 04:09:52,560 on the tree of life right here 2992 04:09:57,050 --> 04:09:54,840 so we study scaling using power laws and 2993 04:09:58,790 --> 04:09:57,060 power laws are found everywhere if we 2994 04:10:00,590 --> 04:09:58,800 consider the number of Web Hits on a web 2995 04:10:02,689 --> 04:10:00,600 page in a given period of time or the 2996 04:10:04,910 --> 04:10:02,699 earthquake magnitude in an area over a 2997 04:10:09,290 --> 04:10:04,920 given period of time many natural and 2998 04:10:13,189 --> 04:10:11,510 so how can we help 2999 04:10:15,530 --> 04:10:13,199 um help us how can this help us 3000 04:10:17,450 --> 04:10:15,540 understand some Concepts in biology for 3001 04:10:19,370 --> 04:10:17,460 that let's consider a Lego set and 3002 04:10:21,950 --> 04:10:19,380 consider the unique pieces in relation 3003 04:10:25,130 --> 04:10:21,960 to the total pieces in the Lego set when 3004 04:10:28,610 --> 04:10:25,140 we plot this on a log log scale 3005 04:10:30,229 --> 04:10:28,620 we see the larger Lego sets use more 3006 04:10:31,910 --> 04:10:30,239 Unique Piece types but they 3007 04:10:33,349 --> 04:10:31,920 progressively go on using lesser 3008 04:10:35,750 --> 04:10:33,359 additional piece types so they're 3009 04:10:38,269 --> 04:10:35,760 becoming more efficient which means the 3010 04:10:40,189 --> 04:10:38,279 larger sets are using uh the same pieces 3011 04:10:42,590 --> 04:10:40,199 the smaller sets are using but in more 3012 04:10:44,750 --> 04:10:42,600 efficient and more complex ways so what 3013 04:10:46,790 --> 04:10:44,760 we're observing in these plots is a 3014 04:10:48,889 --> 04:10:46,800 scaling relationship and when we observe 3015 04:10:50,929 --> 04:10:48,899 a scaling relationship we could say that 3016 04:10:52,250 --> 04:10:50,939 maybe there's a set of rules that's sort 3017 04:10:54,769 --> 04:10:52,260 of governing the way something is 3018 04:10:58,550 --> 04:10:56,870 so you as a power law equation one 3019 04:11:00,889 --> 04:10:58,560 quantity varying as a power law of the 3020 04:11:02,750 --> 04:11:00,899 other and when we plot this on a log log 3021 04:11:05,090 --> 04:11:02,760 scale we get a straight line with the 3022 04:11:06,889 --> 04:11:05,100 slope Alpha so previous Studies have 3023 04:11:08,990 --> 04:11:06,899 shown that genes in a specific 3024 04:11:10,969 --> 04:11:09,000 functional category scale as a power law 3025 04:11:13,250 --> 04:11:10,979 of the total number of genes in a genome 3026 04:11:15,710 --> 04:11:13,260 so for example transcription regulation 3027 04:11:18,710 --> 04:11:15,720 is almost quadratically scaling which 3028 04:11:20,389 --> 04:11:18,720 means if the genome doubles in size the 3029 04:11:22,010 --> 04:11:20,399 genes in this specific category are 3030 04:11:24,229 --> 04:11:22,020 going to quadruple 3031 04:11:26,269 --> 04:11:24,239 so we have tried to include an expanded 3032 04:11:29,030 --> 04:11:26,279 taxonomy in our study and for that we 3033 04:11:30,889 --> 04:11:29,040 use the eggnog database so after power 3034 04:11:32,570 --> 04:11:30,899 of fitting we saw different Trends in 3035 04:11:34,309 --> 04:11:32,580 our data for the smaller and the larger 3036 04:11:36,170 --> 04:11:34,319 genomes so we carried out piecewise 3037 04:11:38,150 --> 04:11:36,180 regression to give Justice to the 3038 04:11:39,889 --> 04:11:38,160 different patterns and scaling observed 3039 04:11:42,050 --> 04:11:39,899 in the plots 3040 04:11:43,790 --> 04:11:42,060 so for example we wanted to capture the 3041 04:11:46,189 --> 04:11:43,800 slope variability for the smaller and 3042 04:11:48,170 --> 04:11:46,199 the larger genome sizes so for example 3043 04:11:50,150 --> 04:11:48,180 in category M which is cell wall and 3044 04:11:52,070 --> 04:11:50,160 cell membrane proteins 3045 04:11:54,110 --> 04:11:52,080 um so the x-axis has the total protein 3046 04:11:55,790 --> 04:11:54,120 annotations and the y-axis has the 3047 04:11:58,670 --> 04:11:55,800 category annotations for that specific 3048 04:12:00,349 --> 04:11:58,680 category so for the smaller genomes we 3049 04:12:02,090 --> 04:12:00,359 can see the proteins are scaling fast 3050 04:12:04,670 --> 04:12:02,100 which means as the genome size is 3051 04:12:06,530 --> 04:12:04,680 increasing they are incorporating 3052 04:12:08,510 --> 04:12:06,540 um more and more proteins faster than 3053 04:12:10,370 --> 04:12:08,520 the larger genomes because after a 3054 04:12:12,710 --> 04:12:10,380 statistically detected breakpoint the 3055 04:12:14,870 --> 04:12:12,720 scaling slows down and we can see a 3056 04:12:18,110 --> 04:12:14,880 similar Trend in category tree category 3057 04:12:20,929 --> 04:12:18,120 T so we saw this trend in most of the 3058 04:12:23,510 --> 04:12:20,939 breakpoints that that were supported in 3059 04:12:25,910 --> 04:12:23,520 bacteria interestingly we observed an 3060 04:12:28,010 --> 04:12:25,920 opposite Trend in archaea the scaling is 3061 04:12:31,010 --> 04:12:28,020 slow in the start but fastens up after 3062 04:12:32,630 --> 04:12:31,020 the statistically detected breakpoint so 3063 04:12:34,610 --> 04:12:32,640 a lot of categories were common between 3064 04:12:36,590 --> 04:12:34,620 archaea and bacteria 3065 04:12:38,030 --> 04:12:36,600 um but there were some categories that 3066 04:12:40,969 --> 04:12:38,040 were exclusively present either in 3067 04:12:42,349 --> 04:12:40,979 archaeon bacteria and it's also 3068 04:12:43,969 --> 04:12:42,359 interesting to observe these differences 3069 04:12:46,910 --> 04:12:43,979 in scaling pattern before and after the 3070 04:12:48,349 --> 04:12:46,920 break point in Ikea and bacteria so we 3071 04:12:50,450 --> 04:12:48,359 thought maybe these differences in 3072 04:12:52,130 --> 04:12:50,460 scaling patterns were caused by phyla 3073 04:12:54,530 --> 04:12:52,140 specific scaling so we broke these 3074 04:12:56,630 --> 04:12:54,540 domains down into specific phyla and 3075 04:12:58,790 --> 04:12:56,640 found great variation in all the phyla 3076 04:13:01,189 --> 04:12:58,800 for all the categories so for example we 3077 04:13:02,990 --> 04:13:01,199 have category 8 here which is coenzyme 3078 04:13:04,490 --> 04:13:03,000 transport proteins 3079 04:13:06,710 --> 04:13:04,500 um which also happens to be the most 3080 04:13:08,689 --> 04:13:06,720 variable across all the phyla 3081 04:13:10,610 --> 04:13:08,699 so we thought maybe this file a specific 3082 04:13:11,929 --> 04:13:10,620 scaling is causing the positioning of 3083 04:13:13,550 --> 04:13:11,939 the breakpoints that we observed 3084 04:13:14,330 --> 04:13:13,560 previously 3085 04:13:16,610 --> 04:13:14,340 um 3086 04:13:18,410 --> 04:13:16,620 so I place these breakpoints on the 3087 04:13:20,689 --> 04:13:18,420 total protein annotations to see if 3088 04:13:22,670 --> 04:13:20,699 there's any specific pattern but we can 3089 04:13:24,229 --> 04:13:22,680 see these individual phyla are spanning 3090 04:13:27,290 --> 04:13:24,239 the breakpoints and there is no specific 3091 04:13:28,910 --> 04:13:27,300 preference of for the break the Filas to 3092 04:13:31,729 --> 04:13:28,920 be present either on either sides of the 3093 04:13:33,110 --> 04:13:31,739 breakpoints so maybe taxonomy is not 3094 04:13:34,910 --> 04:13:33,120 causing the positioning of these 3095 04:13:36,710 --> 04:13:34,920 breakpoints and maybe there are some 3096 04:13:38,210 --> 04:13:36,720 other factors like physiological or 3097 04:13:40,969 --> 04:13:38,220 environmental factors that are causing 3098 04:13:42,769 --> 04:13:40,979 these fake points 3099 04:13:45,530 --> 04:13:42,779 so we were also interested in these 3100 04:13:47,689 --> 04:13:45,540 groups CPR and d-pan uh so these groups 3101 04:13:51,349 --> 04:13:47,699 have extremely small genomes and they 3102 04:13:53,570 --> 04:13:51,359 lack um major metabolic pathways so we 3103 04:13:56,030 --> 04:13:53,580 compared them with um 3104 04:13:58,429 --> 04:13:56,040 eukaryotes unicellular eukaryotes and 3105 04:14:00,229 --> 04:13:58,439 Asgard alkia so for some categories we 3106 04:14:02,389 --> 04:14:00,239 can see the scaling is very similar for 3107 04:14:03,830 --> 04:14:02,399 category o but for some categories the 3108 04:14:06,349 --> 04:14:03,840 scaling is very different like in 3109 04:14:07,969 --> 04:14:06,359 category C which goes on to show there 3110 04:14:10,010 --> 04:14:07,979 are different ways in which an organism 3111 04:14:11,630 --> 04:14:10,020 can adapt while growing in their genome 3112 04:14:12,349 --> 04:14:11,640 sizes 3113 04:14:14,510 --> 04:14:12,359 um 3114 04:14:16,670 --> 04:14:14,520 I've just discussed a few key results in 3115 04:14:18,710 --> 04:14:16,680 my uh talk so if you want to discuss I 3116 04:14:21,050 --> 04:14:18,720 would be interested please come by and 3117 04:14:27,110 --> 04:14:21,060 stop at panel two for the poster thank 3118 04:14:27,120 --> 04:14:32,530 [Applause] 3119 04:14:39,170 --> 04:14:35,030 ly from the University Montana State 3120 04:14:43,250 --> 04:14:40,969 okay so we're gonna shift gears a little 3121 04:14:44,929 --> 04:14:43,260 bit here and so my project largely 3122 04:14:47,510 --> 04:14:44,939 focuses on the evolution of 3123 04:14:50,030 --> 04:14:47,520 multicellularity uh in bacteria 3124 04:14:52,070 --> 04:14:50,040 specifically so titled here cellular 3125 04:14:54,290 --> 04:14:52,080 differentiation within an obligate 3126 04:14:55,610 --> 04:14:54,300 multicellular bacteria 3127 04:14:57,050 --> 04:14:55,620 so where I like to start is just 3128 04:14:59,630 --> 04:14:57,060 generally when we think about the 3129 04:15:01,370 --> 04:14:59,640 evolution of life on Earth we can kind 3130 04:15:05,090 --> 04:15:01,380 of think of it as an increase in 3131 04:15:06,710 --> 04:15:05,100 complexity as as life continued to 3132 04:15:08,990 --> 04:15:06,720 evolve and this is yes and over 3133 04:15:10,969 --> 04:15:09,000 Simplicity but thinking of it as 3134 04:15:12,950 --> 04:15:10,979 molecules coming together to form a 3135 04:15:16,849 --> 04:15:12,960 first cell and eventually getting a 3136 04:15:18,110 --> 04:15:16,859 multi-cellular organism and then some 3137 04:15:20,809 --> 04:15:18,120 something that looks like the life that 3138 04:15:24,290 --> 04:15:20,819 we have on Earth today 3139 04:15:26,090 --> 04:15:24,300 if we look at our classic uh Tree of 3140 04:15:27,650 --> 04:15:26,100 Life where we have different domains of 3141 04:15:31,130 --> 04:15:27,660 the bacteria the archae and the 3142 04:15:32,809 --> 04:15:31,140 eukaryotes generally we tend to think of 3143 04:15:35,510 --> 04:15:32,819 all the multicellular life forms 3144 04:15:37,689 --> 04:15:35,520 belonging to the Eukarya and we think of 3145 04:15:41,809 --> 04:15:37,699 the bacteria and archae as these simple 3146 04:15:46,429 --> 04:15:44,090 um if we look at uh the Tree of Life as 3147 04:15:48,349 --> 04:15:46,439 we know it today uh multicellularity 3148 04:15:51,469 --> 04:15:48,359 actually it can be plotted across the 3149 04:15:55,010 --> 04:15:51,479 entire uh tree of life and so what I'm 3150 04:15:56,870 --> 04:15:55,020 showing here is the aggregative uh 3151 04:15:59,150 --> 04:15:56,880 evolution of multicellularity or a 3152 04:16:01,429 --> 04:15:59,160 clonal uh evolution of multicellularity 3153 04:16:03,469 --> 04:16:01,439 and we see it present in the bacteria 3154 04:16:06,830 --> 04:16:03,479 the archaea and the Eukarya of course 3155 04:16:09,229 --> 04:16:06,840 and so just focusing in on some bacteria 3156 04:16:11,469 --> 04:16:09,239 that are capable of this these are just 3157 04:16:13,729 --> 04:16:11,479 some micrographs showing different 3158 04:16:16,370 --> 04:16:13,739 cyanobacteria that are in those chains 3159 04:16:20,330 --> 04:16:16,380 up there in the upper left and then 3160 04:16:22,790 --> 04:16:20,340 mixopox mixobacteria that sporolate an 3161 04:16:25,610 --> 04:16:22,800 archaea called methanosarcina another 3162 04:16:27,530 --> 04:16:25,620 example is this uh bacteria called cable 3163 04:16:29,330 --> 04:16:27,540 bacteria that form these long centimeter 3164 04:16:31,070 --> 04:16:29,340 long filaments and can actually move 3165 04:16:33,410 --> 04:16:31,080 electrons along that 3166 04:16:35,870 --> 04:16:33,420 so the organism that I study is called 3167 04:16:37,429 --> 04:16:35,880 multicellular magnetotactic bacteria or 3168 04:16:39,229 --> 04:16:37,439 MMB for short because I just don't want 3169 04:16:41,210 --> 04:16:39,239 to say that the whole talk and so this 3170 04:16:44,150 --> 04:16:41,220 is what they look like where we have a 3171 04:16:46,610 --> 04:16:44,160 TM image sewing where these cells are 3172 04:16:50,030 --> 04:16:46,620 grouped together in this kind of 3173 04:16:51,650 --> 04:16:50,040 soccer ball shape or football shape and 3174 04:16:52,910 --> 04:16:51,660 then here in the lower half just an sem 3175 04:16:55,010 --> 04:16:52,920 showing you what that structure looks 3176 04:16:57,590 --> 04:16:55,020 like so I built a cartoon kind of 3177 04:16:59,269 --> 04:16:57,600 showing what this Ultra structure looks 3178 04:17:01,389 --> 04:16:59,279 like and one of the things I want to 3179 04:17:04,250 --> 04:17:01,399 point out that pertains the name is this 3180 04:17:05,689 --> 04:17:04,260 magnetotaxis and so they make these uh 3181 04:17:08,450 --> 04:17:05,699 organelles inside the cells called 3182 04:17:10,849 --> 04:17:08,460 magnetosomes where they synthesize a 3183 04:17:12,710 --> 04:17:10,859 Paramount or ferromagnetic mineral that 3184 04:17:15,110 --> 04:17:12,720 allows them to sense Earth's geomagnetic 3185 04:17:17,929 --> 04:17:15,120 poles and then they can taxi in the 3186 04:17:20,330 --> 04:17:17,939 water column or the sediment column 3187 04:17:22,729 --> 04:17:20,340 um they also have these carbon or energy 3188 04:17:24,650 --> 04:17:22,739 storage granules inside them this 3189 04:17:26,929 --> 04:17:24,660 acellular Center so it's just one layer 3190 04:17:27,769 --> 04:17:26,939 of cells surrounding this acellular 3191 04:17:29,689 --> 04:17:27,779 Center 3192 04:17:31,610 --> 04:17:29,699 and then these actin-like filaments that 3193 04:17:35,030 --> 04:17:31,620 seem to have some something to do with 3194 04:17:39,349 --> 04:17:36,950 um I've referred to them as obligate 3195 04:17:41,210 --> 04:17:39,359 multicellular organisms and this is rare 3196 04:17:43,670 --> 04:17:41,220 in bacteria in fact the only example 3197 04:17:45,650 --> 04:17:43,680 where the hypothesized life cycle is 3198 04:17:48,290 --> 04:17:45,660 that they grow in size and then the 3199 04:17:51,410 --> 04:17:48,300 entire consortia divides and so we don't 3200 04:17:54,189 --> 04:17:51,420 typically see this in bacteria where 3201 04:17:57,290 --> 04:17:54,199 typically we see this this facultative 3202 04:17:59,510 --> 04:17:57,300 multicellularity so they can be a 3203 04:18:01,429 --> 04:17:59,520 multicellular but they can also exist as 3204 04:18:03,710 --> 04:18:01,439 a single cell that's true for all the 3205 04:18:06,110 --> 04:18:03,720 examples I showed you with the tree life 3206 04:18:08,450 --> 04:18:06,120 so here's just an image of uh one of the 3207 04:18:11,450 --> 04:18:08,460 MMB from my sample site and kind of what 3208 04:18:13,969 --> 04:18:11,460 we think it looks like uh MMB dividing 3209 04:18:16,550 --> 04:18:13,979 into possibly three 3210 04:18:18,469 --> 04:18:16,560 I also mentioned moment of truth if the 3211 04:18:23,570 --> 04:18:18,479 video works 3212 04:18:26,090 --> 04:18:23,580 um that they're magnetactic oh let me 3213 04:18:32,330 --> 04:18:26,100 see if I can get this to work 3214 04:18:38,090 --> 04:18:35,469 Okay cool so what we have here is a uh 3215 04:18:41,330 --> 04:18:38,100 tube with the MMB in the bottom of it 3216 04:18:43,189 --> 04:18:41,340 and then a magnetic stir bar next to it 3217 04:18:45,349 --> 04:18:43,199 and if you just watch it you can see 3218 04:18:48,170 --> 04:18:45,359 them swim up out of the bottom of that 3219 04:18:50,269 --> 04:18:48,180 tube and they taxi towards the the stir 3220 04:18:51,590 --> 04:18:50,279 bar these ones are going towards the 3221 04:18:54,889 --> 04:18:51,600 magnetic north 3222 04:18:57,769 --> 04:18:54,899 here in on the right is a hanging water 3223 04:18:58,990 --> 04:18:57,779 droplet just on a coverslip and there's 3224 04:19:01,550 --> 04:18:59,000 a magnet 3225 04:19:04,130 --> 04:19:01,560 to the right and then what I've done is 3226 04:19:05,689 --> 04:19:04,140 just move that magnet turns around they 3227 04:19:06,830 --> 04:19:05,699 start taxing the in the opposite 3228 04:19:08,269 --> 04:19:06,840 direction 3229 04:19:10,130 --> 04:19:08,279 so that's the just showing their 3230 04:19:11,929 --> 04:19:10,140 magnetotaxis 3231 04:19:13,790 --> 04:19:11,939 it helps when we think of 3232 04:19:15,170 --> 04:19:13,800 multicellularity to have some criteria 3233 04:19:17,269 --> 04:19:15,180 for what that is 3234 04:19:19,250 --> 04:19:17,279 and so just a list of these would be 3235 04:19:21,349 --> 04:19:19,260 built from several cells of the same 3236 04:19:23,450 --> 04:19:21,359 species a specific shape and 3237 04:19:25,490 --> 04:19:23,460 organization and synchronized growth so 3238 04:19:28,670 --> 04:19:25,500 that would exclude things like cancer 3239 04:19:30,769 --> 04:19:28,680 no competition between the cells 3240 04:19:33,710 --> 04:19:30,779 coordinated behavior in response to 3241 04:19:36,110 --> 04:19:33,720 external or internal stimuli existence 3242 04:19:38,090 --> 04:19:36,120 of cell to cell signaling and then this 3243 04:19:40,910 --> 04:19:38,100 last one that's kind of like the 3244 04:19:43,510 --> 04:19:40,920 catch-all metabolic differentiation or a 3245 04:19:46,550 --> 04:19:43,520 division of labor so with my organism 3246 04:19:48,650 --> 04:19:46,560 they fit these first four and these 3247 04:19:50,530 --> 04:19:48,660 second the last two are what we're kind 3248 04:19:52,849 --> 04:19:50,540 of looking into 3249 04:19:55,429 --> 04:19:52,859 one of the things we found with our 3250 04:19:58,010 --> 04:19:55,439 project was that the these MMB are not 3251 04:20:00,889 --> 04:19:58,020 actually clonal and how we did this was 3252 04:20:02,990 --> 04:20:00,899 we sorted whole consortias 3253 04:20:04,790 --> 04:20:03,000 did multiple displacement amplifications 3254 04:20:06,590 --> 04:20:04,800 so we Amplified their entire genome and 3255 04:20:08,809 --> 04:20:06,600 sequenced that and we were able to map 3256 04:20:10,790 --> 04:20:08,819 reads to the longest read the best 3257 04:20:13,729 --> 04:20:10,800 assembly there and look at these single 3258 04:20:16,370 --> 04:20:13,739 nucleotide polymorphism differences 3259 04:20:18,050 --> 04:20:16,380 and what we found was that they have 3260 04:20:19,969 --> 04:20:18,060 compared to controls which is a 3261 04:20:22,610 --> 04:20:19,979 pseudomonas control as well as other 3262 04:20:23,830 --> 04:20:22,620 environmental coords they have this much 3263 04:20:26,750 --> 04:20:23,840 higher 3264 04:20:28,550 --> 04:20:26,760 single nucleotide polymorphism rate than 3265 04:20:30,950 --> 04:20:28,560 than what we see with other organisms 3266 04:20:33,010 --> 04:20:30,960 which was kind of a surprise and we're 3267 04:20:36,550 --> 04:20:33,020 still scratching our heads about this 3268 04:20:38,929 --> 04:20:36,560 and that equates to 20 to 100 nucleotide 3269 04:20:40,790 --> 04:20:38,939 polymorphisms in the genome and their 3270 04:20:44,210 --> 04:20:40,800 genomes are about eight megabases which 3271 04:20:46,370 --> 04:20:44,220 is about double that of E coli 3272 04:20:48,050 --> 04:20:46,380 another thing that we looked into was 3273 04:20:50,389 --> 04:20:48,060 this metabolic differentiation or this 3274 04:20:52,490 --> 04:20:50,399 division of labor and this was done by 3275 04:20:54,050 --> 04:20:52,500 doing stable isotope incubations where 3276 04:20:57,710 --> 04:20:54,060 we incubated them in the presence of 3277 04:21:00,670 --> 04:20:57,720 these 13c or deuterium oxide 3278 04:21:03,410 --> 04:21:00,680 um chemicals and then we use a 3279 04:21:07,370 --> 04:21:03,420 nanosecondary ion Mass spectroscopy to 3280 04:21:09,650 --> 04:21:07,380 look at those and map that back where we 3281 04:21:12,110 --> 04:21:09,660 found in the lower left where is the 13c 3282 04:21:14,150 --> 04:21:12,120 image differences in the use of that 3283 04:21:17,030 --> 04:21:14,160 substrate indicating this division of 3284 04:21:19,969 --> 04:21:17,040 labor that we suspected 3285 04:21:22,849 --> 04:21:19,979 so with that just to kind of give 3286 04:21:24,110 --> 04:21:22,859 conclusions and takeaways the m and b 3287 04:21:26,210 --> 04:21:24,120 are the only known obligate 3288 04:21:27,429 --> 04:21:26,220 multicellular bacteria that we know of 3289 04:21:29,929 --> 04:21:27,439 yet 3290 04:21:32,630 --> 04:21:29,939 they are not clonal and do not conform 3291 04:21:35,809 --> 04:21:32,640 to these canonical ideas of what 3292 04:21:37,130 --> 04:21:35,819 multicellular multicellularity is where 3293 04:21:38,150 --> 04:21:37,140 we typically have this clonal 3294 04:21:40,670 --> 04:21:38,160 development 3295 04:21:42,889 --> 04:21:40,680 from where one cell divides into 3296 04:21:45,290 --> 04:21:42,899 daughter cells that stick together or 3297 04:21:46,250 --> 04:21:45,300 this aggregative multicellularity and 3298 04:21:48,710 --> 04:21:46,260 they seem to 3299 04:21:51,170 --> 04:21:48,720 fall somewhere in the middle there 3300 04:21:53,389 --> 04:21:51,180 they also engage in a division of labor 3301 04:21:54,950 --> 04:21:53,399 as we were looking at with the metabolic 3302 04:21:56,870 --> 04:21:54,960 differentiation 3303 04:21:58,189 --> 04:21:56,880 and then of course just to think the lab 3304 04:22:07,070 --> 04:21:58,199 and all the collaborators that help us 3305 04:22:19,130 --> 04:22:09,889 our next speaker is Claire elbon from 3306 04:22:24,590 --> 04:22:22,189 um I'm Claire and so I'm going to talk a 3307 04:22:25,910 --> 04:22:24,600 little bit about respiration oxygen 3308 04:22:28,550 --> 04:22:25,920 sensing 3309 04:22:30,910 --> 04:22:28,560 um and this idea that there might be a 3310 04:22:33,769 --> 04:22:30,920 really close relative to the ancestor of 3311 04:22:36,769 --> 04:22:33,779 protomitochondria in modern oxygen 3312 04:22:41,030 --> 04:22:38,929 um so I think a lot of people here are 3313 04:22:43,910 --> 04:22:41,040 familiar with eukaryogenesis it's this 3314 04:22:45,769 --> 04:22:43,920 idea that an archaea and a bacteria a 3315 04:22:48,710 --> 04:22:45,779 very long time ago decided to be best 3316 04:22:49,729 --> 04:22:48,720 friends forever and now we're here 3317 04:22:52,429 --> 04:22:49,739 um so there's lots of different 3318 04:22:53,630 --> 04:22:52,439 hypotheses over how this might have 3319 04:22:56,210 --> 04:22:53,640 happened 3320 04:22:58,550 --> 04:22:56,220 um and kind of the main point I want to 3321 04:23:01,309 --> 04:22:58,560 make here is that one there's always a 3322 04:23:04,610 --> 04:23:01,319 bacterial host and that's generally 3323 04:23:07,610 --> 04:23:04,620 thought of as an alpha proteobacteria 3324 04:23:10,389 --> 04:23:07,620 um and there's also a lot of or has been 3325 04:23:12,950 --> 04:23:10,399 a lot of talk historically about is this 3326 04:23:15,590 --> 04:23:12,960 obligately aerobic does it have to have 3327 04:23:18,710 --> 04:23:15,600 oxygen is it facultatively aerobic where 3328 04:23:19,610 --> 04:23:18,720 it could use oxygen or not or is it kind 3329 04:23:21,889 --> 04:23:19,620 of 3330 04:23:25,910 --> 04:23:21,899 um an anaerobic partnership that turned 3331 04:23:31,309 --> 04:23:29,030 so a lot of more quantitative Recent 3332 04:23:34,550 --> 04:23:31,319 research so kind of this triangulation 3333 04:23:37,429 --> 04:23:34,560 method suggests that this new clade of 3334 04:23:39,349 --> 04:23:37,439 marine Alpha proteobacteria from marine 3335 04:23:42,710 --> 04:23:39,359 oxiclines and these are really related 3336 04:23:46,309 --> 04:23:42,720 to a group called ioditomonas This is an 3337 04:23:47,689 --> 04:23:46,319 iodide using bacteria might be the 3338 04:23:49,870 --> 04:23:47,699 closest living relative to 3339 04:23:53,210 --> 04:23:49,880 protomitochondria 3340 04:23:55,250 --> 04:23:53,220 and so like I said Alpha proteobacteria 3341 04:23:57,130 --> 04:23:55,260 for a while have been thought of as that 3342 04:23:59,450 --> 04:23:57,140 sort of bacterial component of 3343 04:24:02,150 --> 04:23:59,460 eukaryogenesis and what I'm going to 3344 04:24:04,929 --> 04:24:02,160 showing you really quick right here is 3345 04:24:07,250 --> 04:24:04,939 that these are some anaerobic traits 3346 04:24:09,290 --> 04:24:07,260 that are thought of really essential 3347 04:24:12,650 --> 04:24:09,300 when you're looking at the criteria for 3348 04:24:14,929 --> 04:24:12,660 this ancestor and so most of these are 3349 04:24:17,450 --> 04:24:14,939 alpha proteobacteria and when we're 3350 04:24:19,849 --> 04:24:17,460 looking at the heat map what we want to 3351 04:24:22,490 --> 04:24:19,859 focus on is this green highlighted here 3352 04:24:25,610 --> 04:24:22,500 that's this new clade so they hit all of 3353 04:24:26,630 --> 04:24:25,620 these criteria for anaerobic traits when 3354 04:24:30,229 --> 04:24:26,640 we're thinking about this 3355 04:24:33,889 --> 04:24:31,849 and then when we're thinking more about 3356 04:24:35,809 --> 04:24:33,899 the aerobic side of this these 3357 04:24:38,389 --> 04:24:35,819 facultative aerobics we want to think 3358 04:24:40,309 --> 04:24:38,399 about the terminal electron chain so 3359 04:24:43,370 --> 04:24:40,319 what's interesting is that this is 3360 04:24:46,010 --> 04:24:43,380 comprised of four complexes and these 3361 04:24:48,530 --> 04:24:46,020 complexes actually have this really 3362 04:24:50,870 --> 04:24:48,540 phenomenal history of the evolution of 3363 04:24:54,050 --> 04:24:50,880 respiration inside of it so from complex 3364 04:24:58,670 --> 04:24:54,060 one to complex four we can kind of track 3365 04:25:00,889 --> 04:24:58,680 as the Earth went from anoxic to the 3366 04:25:03,590 --> 04:25:00,899 great oxidation event to kind of what we 3367 04:25:06,830 --> 04:25:03,600 experience now and so I'm really looking 3368 04:25:07,490 --> 04:25:06,840 more at complex four because 3369 04:25:13,729 --> 04:25:07,500 um 3370 04:25:16,189 --> 04:25:13,739 important reduction step so if we're 3371 04:25:18,950 --> 04:25:16,199 thinking about protomitochondria they 3372 04:25:21,410 --> 04:25:18,960 would need to have this complex for so 3373 04:25:24,530 --> 04:25:21,420 that can be divided up even more into 3374 04:25:27,229 --> 04:25:24,540 this a to c family we have an A type 3375 04:25:30,229 --> 04:25:27,239 lots of oxygen we don't have to bind it 3376 04:25:32,570 --> 04:25:30,239 super well it's there but the sea family 3377 04:25:35,750 --> 04:25:32,580 is thought of these as the oldest 3378 04:25:37,490 --> 04:25:35,760 terminal or complex four of the terminal 3379 04:25:40,070 --> 04:25:37,500 electron chain and that's because it's 3380 04:25:43,429 --> 04:25:40,080 capable of binding oxygen at very very 3381 04:25:48,349 --> 04:25:45,769 so for this new clade I had two main 3382 04:25:50,149 --> 04:25:48,359 questions looking at sort of data mining 3383 04:25:52,670 --> 04:25:50,159 which is what kind of genes do they have 3384 04:25:54,649 --> 04:25:52,680 for respiration is it 3385 04:25:56,929 --> 04:25:54,659 um entirely aerobic or is there 3386 04:25:58,849 --> 04:25:56,939 anaerobic as well are they able to sense 3387 04:26:01,250 --> 04:25:58,859 oxygen and are they moving along 3388 04:26:03,229 --> 04:26:01,260 gradients and in response to that and 3389 04:26:06,250 --> 04:26:03,239 then on top of that are these genes 3390 04:26:10,070 --> 04:26:06,260 actually being transcribed 3391 04:26:12,229 --> 04:26:10,080 so I did a lot of data mining in the uh 3392 04:26:13,670 --> 04:26:12,239 with this nice big data set from the 3393 04:26:17,689 --> 04:26:13,680 sandwich Inlet that's in British 3394 04:26:20,090 --> 04:26:17,699 Columbia it's a seasonally hypoxic area 3395 04:26:23,090 --> 04:26:20,100 but it's an oxygen minimum Zone and that 3396 04:26:26,110 --> 04:26:23,100 just means that very quickly we'll lose 3397 04:26:29,149 --> 04:26:26,120 oxygen very high up in the water column 3398 04:26:31,610 --> 04:26:29,159 and it's you can see how like seasonally 3399 04:26:35,330 --> 04:26:31,620 variable it is but overall there's a 3400 04:26:41,990 --> 04:26:38,510 and so the two really interesting points 3401 04:26:44,510 --> 04:26:42,000 I saw was one there are c-type aerobic 3402 04:26:47,750 --> 04:26:44,520 oxidases associated with this Alpha Pro 3403 04:26:49,490 --> 04:26:47,760 nucleate Alpha proteobacteria and its 3404 04:26:52,010 --> 04:26:49,500 transcription or the amount that it was 3405 04:26:54,769 --> 04:26:52,020 being used potentially increased Into 3406 04:26:56,750 --> 04:26:54,779 the anoxic Depths and that there are two 3407 04:26:58,729 --> 04:26:56,760 chemotaxis proteins so that's an 3408 04:27:01,309 --> 04:26:58,739 aerotaxis protein 3409 04:27:02,809 --> 04:27:01,319 maybe maybe not it might be responding 3410 04:27:04,250 --> 04:27:02,819 to something else 3411 04:27:08,269 --> 04:27:04,260 um they were both being transcribed 3412 04:27:10,790 --> 04:27:08,279 really highly into these anoxic depths 3413 04:27:12,370 --> 04:27:10,800 um so my main takeaway is we should look 3414 04:27:14,929 --> 04:27:12,380 at omz's more we're thinking about 3415 04:27:16,910 --> 04:27:14,939 protomitochondria because there are some 3416 04:27:19,130 --> 04:27:16,920 really interesting Alphas there that 3417 04:27:20,870 --> 04:27:19,140 only exist right now as metagenomic 3418 04:27:22,969 --> 04:27:20,880 assembled genomes 3419 04:27:25,189 --> 04:27:22,979 um and it would be really interesting to 3420 04:27:28,010 --> 04:27:25,199 really look at the full genomic uh 3421 04:27:30,110 --> 04:27:28,020 capabilities of them 3422 04:27:31,790 --> 04:27:30,120 um so I'd like to thank the glass Lab at 3423 04:27:35,149 --> 04:27:31,800 Georgia Tech 3424 04:27:38,270 --> 04:27:35,159 um my funding the NSF grad and then the 3425 04:27:47,210 --> 04:27:38,280 oceans across space and time team 3426 04:27:47,220 --> 04:27:50,210 our next speaker 3427 04:27:50,220 --> 04:28:03,889 is Marisa mayor from NASA Ames 3428 04:28:07,189 --> 04:28:05,450 hi there 3429 04:28:09,170 --> 04:28:07,199 okay 3430 04:28:11,229 --> 04:28:09,180 um hi I'm Marissa I'm a postdoc 3431 04:28:14,990 --> 04:28:11,239 currently at NASA Ames Research Center 3432 04:28:17,210 --> 04:28:15,000 and I work on microbial sources of 3433 04:28:19,790 --> 04:28:17,220 hopeenoid lipid biomarkers and different 3434 04:28:21,969 --> 04:28:19,800 hot spring environments uh today I'm 3435 04:28:25,130 --> 04:28:21,979 going to be excitedly sharing with you 3436 04:28:27,229 --> 04:28:25,140 some new potential microbial sources of 3437 04:28:29,649 --> 04:28:27,239 two and three methylhopenoids that we 3438 04:28:33,490 --> 04:28:29,659 were able to find in some of our anoxic 3439 04:28:36,290 --> 04:28:33,500 acidic and sulfitic hydrothermal Springs 3440 04:28:39,769 --> 04:28:36,300 I want to acknowledge my funding sources 3441 04:28:42,649 --> 04:28:39,779 which is oriu NPP program National Park 3442 04:28:44,929 --> 04:28:42,659 Service NASA and finally Stanford 3443 04:28:47,570 --> 04:28:44,939 University because some of this research 3444 04:28:50,330 --> 04:28:47,580 was done back my PhD as well 3445 04:28:52,429 --> 04:28:50,340 um so yeah you might be wondering if you 3446 04:28:54,290 --> 04:28:52,439 are an astronomer or anyone but a lipid 3447 04:28:56,269 --> 04:28:54,300 chemist what are hopeenoids and what do 3448 04:28:57,610 --> 04:28:56,279 they teach us in modern environments why 3449 04:29:00,950 --> 04:28:57,620 should we care 3450 04:29:02,990 --> 04:29:00,960 so opinoids are cyclic triterpenoid 3451 04:29:04,610 --> 04:29:03,000 membrane lipids so they're complex 3452 04:29:06,229 --> 04:29:04,620 they're a little bit different from some 3453 04:29:07,929 --> 04:29:06,239 of the phospholipid membranes we've been 3454 04:29:10,729 --> 04:29:07,939 seeing today 3455 04:29:13,250 --> 04:29:10,739 hopeenoids are some of the most abundant 3456 04:29:15,410 --> 04:29:13,260 bacterial lipid biomarkers on Earth so 3457 04:29:18,950 --> 04:29:15,420 they're very worthy of studying 3458 04:29:22,130 --> 04:29:18,960 they are important geologically they can 3459 04:29:24,290 --> 04:29:22,140 withstand the lithification process and 3460 04:29:27,410 --> 04:29:24,300 all the diagenetic forces that happen 3461 04:29:29,090 --> 04:29:27,420 when you are becoming a fossil and so 3462 04:29:31,250 --> 04:29:29,100 they're actually one of the few really 3463 04:29:33,670 --> 04:29:31,260 strong sources through deep time of 3464 04:29:36,830 --> 04:29:33,680 microbial inputs into the Rock record 3465 04:29:39,170 --> 04:29:36,840 and they can be detected billions of 3466 04:29:42,050 --> 04:29:39,180 years after a deposition 3467 04:29:45,050 --> 04:29:42,060 um finally in modern acidic Springs we 3468 04:29:48,469 --> 04:29:45,060 observe methylated hopeenoids oh sorry 3469 04:29:51,910 --> 04:29:48,479 in in this work we in modern acidic 3470 04:29:54,530 --> 04:29:51,920 Springs observed methylated hofenoids 3471 04:29:57,710 --> 04:29:54,540 and we found these in an anoxic 3472 04:30:00,050 --> 04:29:57,720 environment where no cyanobacteria and 3473 04:30:03,590 --> 04:30:00,060 no methanotrophs were present these are 3474 04:30:06,590 --> 04:30:03,600 kind of the typified known producers of 3475 04:30:09,769 --> 04:30:06,600 these kinds of biomarkers so it was 3476 04:30:11,929 --> 04:30:09,779 exciting to find them at all and yeah 3477 04:30:14,210 --> 04:30:11,939 the work that once we found those 3478 04:30:16,849 --> 04:30:14,220 methylated hopeenoids and the follow-up 3479 04:30:18,889 --> 04:30:16,859 work was able to lead to discovery of 3480 04:30:21,290 --> 04:30:18,899 some new potential Source organisms for 3481 04:30:23,210 --> 04:30:21,300 these lipid biomarkers which if you are 3482 04:30:26,330 --> 04:30:23,220 a biomarker nerd is always exciting and 3483 04:30:28,610 --> 04:30:26,340 it's ever expanding so yeah 3484 04:30:31,370 --> 04:30:28,620 this kind of new evidence of source 3485 04:30:33,649 --> 04:30:31,380 organisms is important because uh these 3486 04:30:35,210 --> 04:30:33,659 yeah kind of inoxic environments and 3487 04:30:37,370 --> 04:30:35,220 knowing about them and the microbes that 3488 04:30:40,189 --> 04:30:37,380 live in them today can have implications 3489 04:30:41,750 --> 04:30:40,199 for us to reinterpret uh the sedimentary 3490 04:30:43,790 --> 04:30:41,760 rock record on Earth but also 3491 04:30:45,889 --> 04:30:43,800 potentially on mars or on other planets 3492 04:30:48,950 --> 04:30:45,899 where we have a sedimentary rock record 3493 04:30:51,110 --> 04:30:48,960 so my samples were taken in two sites 3494 04:30:53,889 --> 04:30:51,120 one is in Yellowstone National Park and 3495 04:30:56,809 --> 04:30:53,899 one is in Lassen Volcanic National Park 3496 04:30:58,550 --> 04:30:56,819 in both Springs you can see the mat is 3497 04:31:02,269 --> 04:30:58,560 kind of similar there's a purple layer 3498 04:31:03,830 --> 04:31:02,279 there's a like a acidic algae layer and 3499 04:31:05,929 --> 04:31:03,840 then there's this white flocculent 3500 04:31:08,710 --> 04:31:05,939 Elemental sulfur on top that's from the 3501 04:31:11,809 --> 04:31:08,720 actual hydrothermal system itself 3502 04:31:14,510 --> 04:31:11,819 so what I did is I go into these Springs 3503 04:31:17,210 --> 04:31:14,520 and I take samples and I go back to my 3504 04:31:19,729 --> 04:31:17,220 lab and I extract for both DNA and for 3505 04:31:20,630 --> 04:31:19,739 lipids and then from there I analyzed 3506 04:31:22,969 --> 04:31:20,640 them 3507 04:31:28,010 --> 04:31:22,979 so I found a bunch of different 3508 04:31:29,570 --> 04:31:28,020 hopeenoids so I did a lcms analysis on 3509 04:31:31,130 --> 04:31:29,580 them and so I was able to actually look 3510 04:31:34,010 --> 04:31:31,140 at the functionalized extended 3511 04:31:36,290 --> 04:31:34,020 hopeenoids and so as you can see there's 3512 04:31:38,149 --> 04:31:36,300 a lot of colors on that graph every 3513 04:31:40,130 --> 04:31:38,159 color is a different type of Hope noid 3514 04:31:43,429 --> 04:31:40,140 uh that was able to find in my Springs 3515 04:31:44,929 --> 04:31:43,439 the green overlay on some of them and 3516 04:31:47,330 --> 04:31:44,939 the pink overlays on some of them 3517 04:31:51,050 --> 04:31:47,340 indicate a 2-methyl for green or a 3518 04:31:52,910 --> 04:31:51,060 three-methyl for pink so we found a huge 3519 04:31:53,630 --> 04:31:52,920 diversity of methylated 3520 04:31:56,330 --> 04:31:53,640 um 3521 04:31:59,149 --> 04:31:56,340 yeah methylated hopeenoid compounds over 3522 04:32:01,429 --> 04:31:59,159 to the far right you can see my controls 3523 04:32:03,410 --> 04:32:01,439 we had pretty low diversity of 3524 04:32:05,090 --> 04:32:03,420 methylated compounds so 3525 04:32:06,769 --> 04:32:05,100 it was really interesting in the 3526 04:32:08,450 --> 04:32:06,779 environmental samples to see so many 3527 04:32:10,070 --> 04:32:08,460 different kinds which is what sent us on 3528 04:32:11,570 --> 04:32:10,080 our DNA work 3529 04:32:14,450 --> 04:32:11,580 um so the first thing that we did was do 3530 04:32:15,889 --> 04:32:14,460 sixness amplicon analysis of our 3531 04:32:18,110 --> 04:32:15,899 extracted DNA 3532 04:32:20,510 --> 04:32:18,120 in that we didn't see any obvious 3533 04:32:23,450 --> 04:32:20,520 sources or classical sources of those 3534 04:32:26,030 --> 04:32:23,460 methylated hopenoids which was pretty 3535 04:32:28,490 --> 04:32:26,040 exciting so that then led us to go back 3536 04:32:29,929 --> 04:32:28,500 and then do some metagenomics and then 3537 04:32:33,769 --> 04:32:29,939 when we were able to analyze that 3538 04:32:35,030 --> 04:32:33,779 metagenomic data we saw many potential 3539 04:32:35,630 --> 04:32:35,040 sources 3540 04:32:39,610 --> 04:32:35,640 um 3541 04:32:42,530 --> 04:32:39,620 of Novel yeah 2-methylhopenoid producers 3542 04:32:46,610 --> 04:32:42,540 mostly anaerobic water and soil dwelling 3543 04:32:48,349 --> 04:32:46,620 microbes but way more sources than are 3544 04:32:52,189 --> 04:32:48,359 currently understood and this is just 3545 04:32:53,990 --> 04:32:52,199 from looking in two hot springs so a 3546 04:32:57,170 --> 04:32:54,000 case for doing field work to expand our 3547 04:32:58,729 --> 04:32:57,180 knowledge in the lab we also saw a ton 3548 04:33:01,550 --> 04:32:58,739 of potential novel sources of three 3549 04:33:03,229 --> 04:33:01,560 methylhopenoids these were also so these 3550 04:33:04,910 --> 04:33:03,239 were mostly anaerobic and acidic 3551 04:33:07,970 --> 04:33:04,920 environment dwellers that we found them 3552 04:33:10,369 --> 04:33:07,980 tagging against and 3553 04:33:13,131 --> 04:33:10,379 yeah it was pretty exciting so if you 3554 04:33:17,029 --> 04:33:13,141 want to know more about either lipids or 3555 04:33:18,709 --> 04:33:17,039 DNA analyzes or a microbial Ecology of 3556 04:33:20,689 --> 04:33:18,719 these acidic Springs please come check 3557 04:33:23,570 --> 04:33:20,699 out my poster later and find me I'll be 3558 04:33:25,670 --> 04:33:23,580 at board 22 at this next session and 3559 04:33:28,789 --> 04:33:25,680 also because I am in a room full of 3560 04:33:31,970 --> 04:33:28,799 early career researchers I coordinate a 3561 04:33:33,949 --> 04:33:31,980 division seminar at NASA Ames and we 3562 04:33:35,929 --> 04:33:33,959 would love to hear you guys give talks 3563 04:33:38,869 --> 04:33:35,939 so if you would like to give a talk at 3564 04:33:40,131 --> 04:33:38,879 NASA Ames at any point please come find 3565 04:33:41,750 --> 04:33:40,141 me at my poster and I'd love to write 3566 04:33:44,269 --> 04:33:41,760 your information down and we would love 3567 04:33:47,150 --> 04:33:44,279 to have you give a talk so 3568 04:33:49,010 --> 04:33:47,970 [Applause] 3569 04:33:53,929 --> 04:33:49,020 [Music] 3570 04:33:57,230 --> 04:33:53,939 [Applause] 3571 04:34:06,590 --> 04:33:57,240 our next speaker is Colin Robinson from 3572 04:34:10,490 --> 04:34:08,631 hi everyone so I'll be talking about 3573 04:34:12,890 --> 04:34:10,500 Martian metabolism and biotic 3574 04:34:14,269 --> 04:34:12,900 perchlorate reduction in Mars analog 3575 04:34:17,570 --> 04:34:14,279 environments on Earth 3576 04:34:18,830 --> 04:34:17,580 so uh since the discovery of let's see 3577 04:34:20,570 --> 04:34:18,840 if I can get this video since the 3578 04:34:22,970 --> 04:34:20,580 discovery of perchlorate 3579 04:34:24,890 --> 04:34:22,980 on Mars by the Phoenix Lander in 2008 3580 04:34:26,810 --> 04:34:24,900 it's been a compound of interest on the 3581 04:34:29,349 --> 04:34:26,820 red planet this is due to its high 3582 04:34:32,090 --> 04:34:29,359 oxidative potential on par with oxygen 3583 04:34:35,390 --> 04:34:32,100 which means that it's a potential energy 3584 04:34:37,369 --> 04:34:35,400 source for life on the red planet uh on 3585 04:34:39,230 --> 04:34:37,379 Mars it's ubiquitous in Martian regolith 3586 04:34:40,310 --> 04:34:39,240 reaching concentrations of 0.5 weight 3587 04:34:43,010 --> 04:34:40,320 percentage 3588 04:34:44,990 --> 04:34:43,020 on Earth there are microbes that reduce 3589 04:34:46,369 --> 04:34:45,000 perchlorate in place of oxygen and 3590 04:34:48,051 --> 04:34:46,379 Metabolism using it to drive the 3591 04:34:50,869 --> 04:34:48,061 electron transport chain 3592 04:34:52,849 --> 04:34:50,879 and perchlorate accumulates in Mars 3593 04:34:54,230 --> 04:34:52,859 analog systems on Earth such as the 3594 04:34:56,869 --> 04:34:54,240 Atacama Desert where it reaches 3595 04:34:58,609 --> 04:34:56,879 concentrations up to 0.18 percent 3596 04:34:59,830 --> 04:34:58,619 as well as the Antarctic dry valleys 3597 04:35:02,929 --> 04:34:59,840 where it reaches concentrations up to 3598 04:35:04,849 --> 04:35:02,939 .0038 these are Mars analog systems that 3599 04:35:08,029 --> 04:35:04,859 are incredibly dry and accumulate 3600 04:35:11,929 --> 04:35:08,039 perchlorate via atmospheric deposition 3601 04:35:14,869 --> 04:35:11,939 over long time scales and uh 3602 04:35:16,789 --> 04:35:14,879 there are likely at looking at these 3603 04:35:19,131 --> 04:35:16,799 systems it seems reasonable that 3604 04:35:20,510 --> 04:35:19,141 reducing microbes might evolve and 3605 04:35:23,449 --> 04:35:20,520 persist in these types of environments 3606 04:35:25,609 --> 04:35:23,459 however the model organisms that we use 3607 04:35:27,650 --> 04:35:25,619 to study biotic perchlorate reduction 3608 04:35:31,310 --> 04:35:27,660 don't come from Mars analog environments 3609 04:35:34,369 --> 04:35:31,320 they come from the Potomac River in 3610 04:35:36,590 --> 04:35:34,379 Washington DC where there's very little 3611 04:35:38,689 --> 04:35:36,600 to no natural perchlorate that 3612 04:35:43,131 --> 04:35:38,699 accumulates all the pakori that we do 3613 04:35:44,631 --> 04:35:43,141 find here is um is waste from Munitions 3614 04:35:46,670 --> 04:35:44,641 factories that gets dumped into the 3615 04:35:49,010 --> 04:35:46,680 river so how did perchlorate reducing 3616 04:35:50,170 --> 04:35:49,020 microbes arrive in this type of 3617 04:35:52,789 --> 04:35:50,180 environment 3618 04:35:54,289 --> 04:35:52,799 if they likely didn't evolve here due to 3619 04:35:56,750 --> 04:35:54,299 the lack of perchloride 3620 04:35:58,131 --> 04:35:56,760 well we know that the perchlorate 3621 04:36:00,830 --> 04:35:58,141 reduction genomic island is widely 3622 04:36:02,150 --> 04:36:00,840 spread via horizontal Gene transfer we 3623 04:36:04,490 --> 04:36:02,160 know this because when we look at 3624 04:36:06,890 --> 04:36:04,500 reducing organisms uh can you see my 3625 04:36:09,650 --> 04:36:06,900 mouse yeah there we go 3626 04:36:10,910 --> 04:36:09,660 um the elements required for biotic 3627 04:36:13,070 --> 04:36:10,920 report reduction the genes that are 3628 04:36:14,990 --> 04:36:13,080 required for court reduction 3629 04:36:16,609 --> 04:36:15,000 um share a lot of homology between the 3630 04:36:20,269 --> 04:36:16,619 genes but where the genes are situated 3631 04:36:21,529 --> 04:36:20,279 in the genome is very diverse depending 3632 04:36:25,609 --> 04:36:21,539 on the organism that you're looking at 3633 04:36:27,349 --> 04:36:25,619 so it's a very chimeric metabolism so if 3634 04:36:29,150 --> 04:36:27,359 we look here the the bright green that's 3635 04:36:30,470 --> 04:36:29,160 chloride dismutates and this long dark 3636 04:36:32,090 --> 04:36:30,480 green that's perchlorate reductase 3637 04:36:34,269 --> 04:36:32,100 they're always kind of in different 3638 04:36:37,189 --> 04:36:34,279 configurations in relation to each other 3639 04:36:38,810 --> 04:36:37,199 in uh in the genomic Island and that's 3640 04:36:43,010 --> 04:36:38,820 because these individual elements are 3641 04:36:44,929 --> 04:36:43,020 getting passed uh individually and um 3642 04:36:47,269 --> 04:36:44,939 independently of one another via 3643 04:36:49,910 --> 04:36:47,279 horizontal Gene transfer so you only get 3644 04:36:53,390 --> 04:36:49,920 reducing microbes when these elements 3645 04:36:55,429 --> 04:36:53,400 come together in the same organism 3646 04:36:57,709 --> 04:36:55,439 so my research question was did 3647 04:36:59,029 --> 04:36:57,719 canonical biotic reduction arise in 3648 04:37:01,070 --> 04:36:59,039 these Mars analog environments like the 3649 04:37:02,990 --> 04:37:01,080 Atacama Desert or Antarctic dry valleys 3650 04:37:05,449 --> 04:37:03,000 and then disperse around the world via 3651 04:37:07,970 --> 04:37:05,459 acellular and microbial dispersal 3652 04:37:09,709 --> 04:37:07,980 so in order to test that I selected 3653 04:37:11,869 --> 04:37:09,719 metagenomes from sites around the world 3654 04:37:13,849 --> 04:37:11,879 the metagenome for those of you who 3655 04:37:15,529 --> 04:37:13,859 don't know is basically all the DNA in a 3656 04:37:18,890 --> 04:37:15,539 sample it comes in little 3657 04:37:21,230 --> 04:37:18,900 20 base pair of chunks and you have to 3658 04:37:22,609 --> 04:37:21,240 piece them together like a puzzle and 3659 04:37:24,949 --> 04:37:22,619 then pick out the puzzles that you're 3660 04:37:27,890 --> 04:37:24,959 interested in that maybe make a picture 3661 04:37:29,449 --> 04:37:27,900 you're interested in and then uh and 3662 04:37:31,250 --> 04:37:29,459 then analyze those independent of the 3663 04:37:33,109 --> 04:37:31,260 rest of the metagenome so basically what 3664 04:37:35,209 --> 04:37:33,119 I did is I selected metagenomes from 3665 04:37:37,189 --> 04:37:35,219 sites around the world I analyzed the 3666 04:37:39,170 --> 04:37:37,199 presence of reduction genes so basically 3667 04:37:41,209 --> 04:37:39,180 build the little puzzles and then pulled 3668 04:37:42,830 --> 04:37:41,219 out the the ones that made reducing 3669 04:37:45,590 --> 04:37:42,840 genes and then I calculated the 3670 04:37:48,349 --> 04:37:45,600 phylogenetic diversity of those genes at 3671 04:37:49,849 --> 04:37:48,359 each site this is a study that has 3672 04:37:52,670 --> 04:37:49,859 really up until this point been done 3673 04:37:55,250 --> 04:37:52,680 only in humans which is this uh type of 3674 04:37:57,109 --> 04:37:55,260 analysis where we look at diversity of a 3675 04:37:58,670 --> 04:37:57,119 species or a gene to determine the 3676 04:38:00,289 --> 04:37:58,680 likely places where it's persisted the 3677 04:38:02,269 --> 04:38:00,299 longest that's how we know that humans 3678 04:38:03,529 --> 04:38:02,279 come out of Africa is because most of 3679 04:38:05,869 --> 04:38:03,539 our phylogenetic diversity can be 3680 04:38:09,109 --> 04:38:05,879 accounted for in Africa 3681 04:38:10,429 --> 04:38:09,119 so when I did this uh so this is for 3682 04:38:12,410 --> 04:38:10,439 chloride dismutase a gene that's 3683 04:38:16,189 --> 04:38:12,420 involved in perchlorate reduction I 3684 04:38:18,650 --> 04:38:16,199 found the highest diversity to be in uh 3685 04:38:20,750 --> 04:38:18,660 in the Antarctic dry Valley so what 3686 04:38:22,849 --> 04:38:20,760 we're seeing here is these bars are are 3687 04:38:24,590 --> 04:38:22,859 a scale that's Faith's phylogenetic 3688 04:38:27,051 --> 04:38:24,600 diversity zero is basically zero 3689 04:38:29,209 --> 04:38:27,061 diversity and then up to 50 would would 3690 04:38:30,410 --> 04:38:29,219 be the maximum amount of diversity in 3691 04:38:33,529 --> 04:38:30,420 these genes that we see and each of 3692 04:38:34,730 --> 04:38:33,539 these blue dots is a separate metagenome 3693 04:38:37,551 --> 04:38:34,740 um as you can see there's a little bit 3694 04:38:39,769 --> 04:38:37,561 of sampling bias because in the anterior 3695 04:38:40,789 --> 04:38:39,779 dry valleys or Atacama Desert we have a 3696 04:38:42,051 --> 04:38:40,799 lot more sampling there's a lot more 3697 04:38:43,551 --> 04:38:42,061 research that happens in these sites 3698 04:38:45,590 --> 04:38:43,561 we've got a lot more metagenomes that I 3699 04:38:47,390 --> 04:38:45,600 can analyze whereas if I look at other 3700 04:38:49,609 --> 04:38:47,400 Mars analog sites like the Namib Desert 3701 04:38:52,609 --> 04:38:49,619 there are quite a few less or in South 3702 04:38:54,170 --> 04:38:52,619 Australian desert uh much less access to 3703 04:38:56,330 --> 04:38:54,180 that kind of data 3704 04:38:57,650 --> 04:38:56,340 when I looked at procore reductase 3705 04:39:00,650 --> 04:38:57,660 another Gene involved in biotic 3706 04:39:02,449 --> 04:39:00,660 reduction we also see that it is it 3707 04:39:04,789 --> 04:39:02,459 reaches highest levels in the Antarctic 3708 04:39:06,590 --> 04:39:04,799 dry valleys so that basically indicates 3709 04:39:08,990 --> 04:39:06,600 that these genes have persisted the 3710 04:39:11,510 --> 04:39:09,000 longest in in these in this in these in 3711 04:39:13,250 --> 04:39:11,520 these Mars analog ecosystems supporting 3712 04:39:15,170 --> 04:39:13,260 the claim that these may have evolved 3713 04:39:16,131 --> 04:39:15,180 and persisted in those Mars analog 3714 04:39:18,529 --> 04:39:16,141 systems 3715 04:39:19,849 --> 04:39:18,539 so some conclusions for court reduction 3716 04:39:21,650 --> 04:39:19,859 genes are present and diverse in Mars 3717 04:39:23,750 --> 04:39:21,660 analog systems that's really awesome 3718 04:39:25,789 --> 04:39:23,760 right before we didn't even know if they 3719 04:39:27,529 --> 04:39:25,799 could persist in Wars analog systems but 3720 04:39:29,810 --> 04:39:27,539 it looks like they both evolve and 3721 04:39:31,310 --> 04:39:29,820 persist there for long time scales 3722 04:39:33,109 --> 04:39:31,320 this metabolism may have evolved in 3723 04:39:34,369 --> 04:39:33,119 these environments and then uh prior to 3724 04:39:36,769 --> 04:39:34,379 dispersing around the world via 3725 04:39:38,330 --> 04:39:36,779 acellular and microbial dispersal and 3726 04:39:40,490 --> 04:39:38,340 studying for core reducing organisms in 3727 04:39:41,690 --> 04:39:40,500 Mars analog environments can give us 3728 04:39:43,850 --> 04:39:41,700 further insight into how life may 3729 04:39:45,830 --> 04:39:43,860 persist on the red planet when we're 3730 04:39:47,390 --> 04:39:45,840 studying life forms that do metabolisms 3731 04:39:48,530 --> 04:39:47,400 like what we expect to find on Mars we 3732 04:39:50,150 --> 04:39:48,540 shouldn't be looking at organisms that 3733 04:39:52,070 --> 04:39:50,160 come out of the Potomac River we should 3734 04:39:53,448 --> 04:39:52,080 be looking at at organisms in these Mars 3735 04:39:56,448 --> 04:39:53,458 analog systems 3736 04:39:59,030 --> 04:39:56,458 so I'd like to hear some some people I'd 3737 04:40:00,890 --> 04:39:59,040 like to thank so my funding which is the 3738 04:40:03,170 --> 04:40:00,900 the NSF grant for long-term ecological 3739 04:40:04,788 --> 04:40:03,180 research at McMurdo Station uh my 3740 04:40:06,708 --> 04:40:04,798 department at Brigham Young University 3741 04:40:09,110 --> 04:40:06,718 as well as the help and advice of Dr 3742 04:40:10,788 --> 04:40:09,120 John Coates at UC Berkeley Dr Kendall 3743 04:40:12,830 --> 04:40:10,798 Kendall Lynch at the lunar and planetary 3744 04:40:15,060 --> 04:40:12,840 Institute and Dr Jennifer glass at 3745 04:40:22,910 --> 04:40:15,070 Georgia Tech so thank you 3746 04:40:25,610 --> 04:40:22,920 [Applause] 3747 04:40:36,410 --> 04:40:25,620 and our last speaker is seleth Pandey 3748 04:40:41,208 --> 04:40:38,930 hello everyone I am Siddharth from jet 3749 04:40:42,830 --> 04:40:41,218 propulsion laboratory and I'm here to 3750 04:40:44,750 --> 04:40:42,840 talk about the work that I started 3751 04:40:46,910 --> 04:40:44,760 before joining JPL 3752 04:40:49,250 --> 04:40:46,920 um in India and for those of you in the 3753 04:40:51,708 --> 04:40:49,260 audience who are currently involved or 3754 04:40:53,868 --> 04:40:51,718 plan to do work in different parts of 3755 04:40:55,670 --> 04:40:53,878 the world where astrobiology has huge 3756 04:40:58,130 --> 04:40:55,680 potential and significance hopefully 3757 04:41:00,110 --> 04:40:58,140 with some of my experience you'll be 3758 04:41:02,208 --> 04:41:00,120 able to take things forward 3759 04:41:04,670 --> 04:41:02,218 so first of all a little bit about 3760 04:41:06,530 --> 04:41:04,680 myself so I'm originally from India and 3761 04:41:08,690 --> 04:41:06,540 before joining JPL 3762 04:41:11,090 --> 04:41:08,700 um I have an engineering background and 3763 04:41:12,590 --> 04:41:11,100 my current work is actually on Enceladus 3764 04:41:13,970 --> 04:41:12,600 on Sample collection Technologies but 3765 04:41:15,770 --> 04:41:13,980 unfortunately today I'm not going to be 3766 04:41:17,090 --> 04:41:15,780 talking about that this is primarily 3767 04:41:18,650 --> 04:41:17,100 going to be focused on that but just 3768 04:41:20,990 --> 04:41:18,660 giving a heads up people can find me 3769 04:41:23,150 --> 04:41:21,000 after the talk and maybe we can chat 3770 04:41:26,330 --> 04:41:23,160 um but here here is why we focused on 3771 04:41:27,830 --> 04:41:26,340 India well first and foremost as a 3772 04:41:29,750 --> 04:41:27,840 country India has one of the largest 3773 04:41:31,910 --> 04:41:29,760 student populations as some of you might 3774 04:41:33,650 --> 04:41:31,920 be aware every year we've got several 3775 04:41:35,390 --> 04:41:33,660 thousands of students graduating in 3776 04:41:38,090 --> 04:41:35,400 science and engineering and on a daily 3777 04:41:39,110 --> 04:41:38,100 basis we get inquiries about how do you 3778 04:41:40,970 --> 04:41:39,120 study and how do you work in 3779 04:41:42,770 --> 04:41:40,980 astrobiology so there's a huge supply 3780 04:41:45,890 --> 04:41:42,780 and demand problem and there's little to 3781 04:41:47,930 --> 04:41:45,900 no formal education or you know career 3782 04:41:49,570 --> 04:41:47,940 prospects in the country so that was the 3783 04:41:52,550 --> 04:41:49,580 first and foremost no-brainer reason 3784 04:41:54,170 --> 04:41:52,560 secondly I would like to really promote 3785 04:41:57,350 --> 04:41:54,180 the fact that we have an amazing 3786 04:41:58,970 --> 04:41:57,360 diversity of high value science analogs 3787 04:42:00,590 --> 04:41:58,980 and these are places where some of you 3788 04:42:03,230 --> 04:42:00,600 might actually find some of your work to 3789 04:42:05,330 --> 04:42:03,240 be super relevant so with this in mind 3790 04:42:06,830 --> 04:42:05,340 these sites are not even on the atlas of 3791 04:42:08,510 --> 04:42:06,840 astrobiology sites that the community 3792 04:42:11,448 --> 04:42:08,520 normally works in 3793 04:42:13,610 --> 04:42:11,458 and lastly our National Space Agency 3794 04:42:16,310 --> 04:42:13,620 Indian space research organization is 3795 04:42:18,948 --> 04:42:16,320 finally reaching a point to to involve 3796 04:42:21,170 --> 04:42:18,958 astrobiology as an important science 3797 04:42:23,030 --> 04:42:21,180 priority for its future missions it had 3798 04:42:25,368 --> 04:42:23,040 the Mars Orbiter mission in 2014 3799 04:42:26,990 --> 04:42:25,378 currently there are it's under Works to 3800 04:42:29,090 --> 04:42:27,000 work on a Surface mission that would 3801 04:42:30,830 --> 04:42:29,100 work on the progress and the success of 3802 04:42:32,990 --> 04:42:30,840 the lunar mission that will be launching 3803 04:42:34,670 --> 04:42:33,000 in a month from now and finally there is 3804 04:42:37,190 --> 04:42:34,680 the gaganyan program which is the human 3805 04:42:39,288 --> 04:42:37,200 space program which will have astronauts 3806 04:42:41,810 --> 04:42:39,298 working in low earth orbit 3807 04:42:43,610 --> 04:42:41,820 so that's with that as the basic 3808 04:42:45,650 --> 04:42:43,620 motivation of why we decided to do this 3809 04:42:47,868 --> 04:42:45,660 seven years ago let me talk quickly 3810 04:42:49,970 --> 04:42:47,878 about the background in terms of what 3811 04:42:52,368 --> 04:42:49,980 astrobiology was happening before we 3812 04:42:55,010 --> 04:42:52,378 kind of stepped in so the earliest what 3813 04:42:56,930 --> 04:42:55,020 we could find is between 97 to 2005 3814 04:42:58,788 --> 04:42:56,940 Israel was involved in scientific 3815 04:43:01,368 --> 04:42:58,798 balloon experiments where they were 3816 04:43:03,350 --> 04:43:01,378 basically working on collecting and 3817 04:43:05,628 --> 04:43:03,360 understanding microbes in the 3818 04:43:08,448 --> 04:43:05,638 stratosphere 3819 04:43:09,890 --> 04:43:08,458 um cut to 2015 whereas a grad student I 3820 04:43:12,050 --> 04:43:09,900 got an opportunity to go on an 3821 04:43:14,868 --> 04:43:12,060 astrobiology expedition to New Zealand 3822 04:43:17,270 --> 04:43:14,878 and along with a few other Indian and 3823 04:43:19,250 --> 04:43:17,280 Indian origin researchers we decided to 3824 04:43:22,330 --> 04:43:19,260 bring the program to India 3825 04:43:25,490 --> 04:43:22,340 and that's what we did as part of the 3826 04:43:27,050 --> 04:43:25,500 NASA spacer down India Expedition that 3827 04:43:28,788 --> 04:43:27,060 was the first time that a dedicated 3828 04:43:30,110 --> 04:43:28,798 astrobiology expedition was taking place 3829 04:43:32,628 --> 04:43:30,120 Gathering and bringing together 3830 04:43:34,430 --> 04:43:32,638 researchers in the country and that's 3831 04:43:36,470 --> 04:43:34,440 where ball just really started rolling 3832 04:43:38,990 --> 04:43:36,480 the momentum started building up and let 3833 04:43:40,788 --> 04:43:39,000 me tell you something that working and 3834 04:43:43,310 --> 04:43:40,798 socializing with people in uncomfortable 3835 04:43:45,170 --> 04:43:43,320 dry desert environments is way better 3836 04:43:47,090 --> 04:43:45,180 than inside an air-conditioned classroom 3837 04:43:49,368 --> 04:43:47,100 with experience 3838 04:43:50,990 --> 04:43:49,378 so some of the things that led from that 3839 04:43:52,550 --> 04:43:51,000 was the establishment of a standard of 3840 04:43:53,930 --> 04:43:52,560 Excellence in astrobiology at Amity 3841 04:43:56,150 --> 04:43:53,940 University Mumbai which was the first 3842 04:43:58,490 --> 04:43:56,160 dedicated Center that I was a part of 3843 04:43:59,990 --> 04:43:58,500 leading and also as part of Blue Marble 3844 04:44:02,570 --> 04:44:00,000 space the organization that I had been 3845 04:44:04,670 --> 04:44:02,580 affiliated with the astrobiology India 3846 04:44:07,070 --> 04:44:04,680 group has been active since then 3847 04:44:09,590 --> 04:44:07,080 working to promote coordination 3848 04:44:10,970 --> 04:44:09,600 activities between domestic researchers 3849 04:44:12,708 --> 04:44:10,980 in the country so we've been having 3850 04:44:15,288 --> 04:44:12,718 National level meetings and discussions 3851 04:44:17,090 --> 04:44:15,298 and what we want to do from here is move 3852 04:44:19,250 --> 04:44:17,100 forward towards setting up a national 3853 04:44:21,590 --> 04:44:19,260 astrobiology program closely in support 3854 04:44:23,390 --> 04:44:21,600 with the Indian government 3855 04:44:26,090 --> 04:44:23,400 I don't have enough time but I'll try to 3856 04:44:27,590 --> 04:44:26,100 do justice to this slide our efforts at 3857 04:44:30,830 --> 04:44:27,600 the center focused on three main 3858 04:44:32,810 --> 04:44:30,840 verticals the microgravity research we 3859 04:44:35,150 --> 04:44:32,820 built plant-based plant growth 3860 04:44:36,288 --> 04:44:35,160 observation experiments for ISRO we 3861 04:44:38,330 --> 04:44:36,298 worked on characterizing some of the 3862 04:44:40,910 --> 04:44:38,340 sites in ladakh which is an early Mars 3863 04:44:43,550 --> 04:44:40,920 analog and Hardware testing for Rovers 3864 04:44:45,650 --> 04:44:43,560 and in collaboration with UC Berkeley 3865 04:44:47,090 --> 04:44:45,660 the Berkeley City Research Center we had 3866 04:44:48,770 --> 04:44:47,100 four research fellows who were working 3867 04:44:51,470 --> 04:44:48,780 to use 3868 04:44:53,750 --> 04:44:51,480 um radio telescope data from gmrt which 3869 04:44:55,070 --> 04:44:53,760 is a array facility there to set up a 3870 04:44:57,650 --> 04:44:55,080 city pipeline 3871 04:44:59,390 --> 04:44:57,660 and our research work has culminated 3872 04:45:01,250 --> 04:44:59,400 into the university finally agreeing to 3873 04:45:02,570 --> 04:45:01,260 have a master's program that is 3874 04:45:04,670 --> 04:45:02,580 dedicated for astrology and science 3875 04:45:06,170 --> 04:45:04,680 students so hopefully this year onwards 3876 04:45:09,050 --> 04:45:06,180 we'll have students in India who'll have 3877 04:45:11,090 --> 04:45:09,060 that opportunity to study there 3878 04:45:13,610 --> 04:45:11,100 um Blue Marble space has been a great 3879 04:45:14,750 --> 04:45:13,620 source of information and help and 3880 04:45:16,850 --> 04:45:14,760 network so those of you are not 3881 04:45:19,128 --> 04:45:16,860 affiliated I would say strongly 3882 04:45:21,110 --> 04:45:19,138 recommended do consider it 3883 04:45:23,510 --> 04:45:21,120 quickly talking about some of the unique 3884 04:45:25,010 --> 04:45:23,520 aspects of Astral biology in India I've 3885 04:45:27,830 --> 04:45:25,020 just highlighted some of the main sites 3886 04:45:29,690 --> 04:45:27,840 here in ladakh up north which is a high 3887 04:45:31,310 --> 04:45:29,700 altitude code dry desert environment 3888 04:45:33,948 --> 04:45:31,320 Kutch which is one of the largest salt 3889 04:45:36,470 --> 04:45:33,958 flats in the world the only accessible 3890 04:45:37,970 --> 04:45:36,480 Basalt impact Creator in loner the 3891 04:45:39,470 --> 04:45:37,980 basalt traps and Limestone caves and 3892 04:45:41,330 --> 04:45:39,480 there are several others 3893 04:45:44,030 --> 04:45:41,340 and because we don't have a National 3894 04:45:44,930 --> 04:45:44,040 astrobiology Institute yet there have 3895 04:45:47,230 --> 04:45:44,940 been institutions that have been 3896 04:45:50,510 --> 04:45:47,240 mushrooming over the last few decades 3897 04:45:53,930 --> 04:45:50,520 and I've been very successful and 3898 04:45:56,150 --> 04:45:53,940 fortunate to be part of several senior 3899 04:45:58,490 --> 04:45:56,160 earth scientists to work towards setting 3900 04:46:00,110 --> 04:45:58,500 this up and it's only because of these 3901 04:46:02,208 --> 04:46:00,120 people who you're seeing on the screen 3902 04:46:03,590 --> 04:46:02,218 over here that we're able to do this and 3903 04:46:05,448 --> 04:46:03,600 we've been working through the pandemic 3904 04:46:07,070 --> 04:46:05,458 to make this happen they've been a 3905 04:46:08,690 --> 04:46:07,080 working group several working groups 3906 04:46:11,090 --> 04:46:08,700 that have been put in place uh we've 3907 04:46:13,070 --> 04:46:11,100 been closely following work done in 3908 04:46:14,868 --> 04:46:13,080 Europe and at uh in the United States 3909 04:46:17,030 --> 04:46:14,878 through the NASA Astra Biology Institute 3910 04:46:18,890 --> 04:46:17,040 to help form these working groups and 3911 04:46:20,990 --> 04:46:18,900 these are some names in some areas where 3912 04:46:23,750 --> 04:46:21,000 you know people have been working 3913 04:46:25,310 --> 04:46:23,760 and too much information bad slide I 3914 04:46:27,470 --> 04:46:25,320 know but I just wanted to tell you that 3915 04:46:29,090 --> 04:46:27,480 there are these sites and we have been 3916 04:46:31,610 --> 04:46:29,100 trying to map out the science objectives 3917 04:46:33,050 --> 04:46:31,620 the different Technologies what worlds 3918 04:46:34,730 --> 04:46:33,060 are they analog to and what kind of 3919 04:46:36,770 --> 04:46:34,740 missions would they be able to support 3920 04:46:38,090 --> 04:46:36,780 into the future 3921 04:46:40,190 --> 04:46:38,100 um some other ways in which we have been 3922 04:46:42,410 --> 04:46:40,200 contributing we published our first 3923 04:46:43,368 --> 04:46:42,420 advocacy paper in new space Journal uh 3924 04:46:45,948 --> 04:46:43,378 talking about the importance of 3925 04:46:47,690 --> 04:46:45,958 astrobiology for India and internally we 3926 04:46:50,090 --> 04:46:47,700 have been contributing to the science 3927 04:46:52,850 --> 04:46:50,100 roadmap for ISRO as well 3928 04:46:54,410 --> 04:46:52,860 now three main wins for us one is the 3929 04:46:56,628 --> 04:46:54,420 fact that we've got several students who 3930 04:46:57,830 --> 04:46:56,638 have gone through our uh system and 3931 04:47:00,590 --> 04:46:57,840 these are the people who in the future 3932 04:47:02,390 --> 04:47:00,600 will be taking the light forward 3933 04:47:04,850 --> 04:47:02,400 this year ISRO published its space 3934 04:47:06,770 --> 04:47:04,860 policy document and we were very happy 3935 04:47:08,990 --> 04:47:06,780 to see that they have acknowledged the 3936 04:47:10,490 --> 04:47:09,000 importance of estrobiology because 3937 04:47:11,510 --> 04:47:10,500 they've mentioned that they will be 3938 04:47:13,910 --> 04:47:11,520 looking into extraterrestrial 3939 04:47:15,830 --> 04:47:13,920 habitability so for us as a country this 3940 04:47:17,090 --> 04:47:15,840 is a huge win that finally ISRO has 3941 04:47:19,788 --> 04:47:17,100 acknowledged us 3942 04:47:22,190 --> 04:47:19,798 and the fact that there is now 3943 04:47:24,890 --> 04:47:22,200 comprehensive I would say not enough but 3944 04:47:26,750 --> 04:47:24,900 still comprehensive diversification of 3945 04:47:28,550 --> 04:47:26,760 funding for scientists in the country to 3946 04:47:29,750 --> 04:47:28,560 do this but definitely more work needs 3947 04:47:30,650 --> 04:47:29,760 to be done and more funding needs to be 3948 04:47:33,530 --> 04:47:30,660 put together 3949 04:47:35,030 --> 04:47:33,540 so my last slide um to summarize some of 3950 04:47:36,470 --> 04:47:35,040 these things if you are in your region 3951 04:47:38,390 --> 04:47:36,480 or country interested in setting things 3952 04:47:39,708 --> 04:47:38,400 up the first and foremost step is to 3953 04:47:41,930 --> 04:47:39,718 bring early and mid-career people 3954 04:47:44,448 --> 04:47:41,940 together and encourage conversations to 3955 04:47:46,190 --> 04:47:44,458 take place at a domestic level at the 3956 04:47:48,470 --> 04:47:46,200 same time leveraging International work 3957 04:47:50,868 --> 04:47:48,480 and like I said field workshops are 3958 04:47:52,970 --> 04:47:50,878 amazing for team building 3959 04:47:55,070 --> 04:47:52,980 finding an important University or a 3960 04:47:56,810 --> 04:47:55,080 host institution is critical because if 3961 04:47:58,310 --> 04:47:56,820 you're doing events logistically 3962 04:48:00,410 --> 04:47:58,320 speaking it's important to find an 3963 04:48:01,850 --> 04:48:00,420 organization that will support you and 3964 04:48:03,530 --> 04:48:01,860 beware of non-scientific and 3965 04:48:04,430 --> 04:48:03,540 exploitative groups in the in the in the 3966 04:48:06,708 --> 04:48:04,440 region 3967 04:48:08,868 --> 04:48:06,718 finally convene workshops identify 3968 04:48:11,330 --> 04:48:08,878 research interests try to tiler them 3969 04:48:12,890 --> 04:48:11,340 together into overarching themes and 3970 04:48:14,628 --> 04:48:12,900 help the group formalize themselves in 3971 04:48:16,850 --> 04:48:14,638 the form of virtual Network a non-profit 3972 04:48:18,288 --> 04:48:16,860 or a society and finally encourage the 3973 04:48:19,910 --> 04:48:18,298 group members to work closely with their 3974 04:48:22,190 --> 04:48:19,920 government for their astrology goals so 3975 04:48:23,750 --> 04:48:22,200 that's my time and you hope you can find 3976 04:48:25,380 --> 04:48:23,760 me and those of you are interested can 3977 04:48:34,788 --> 04:48:25,390 talk more on this thank you 3978 04:48:37,550 --> 04:48:34,798 [Applause] 3979 04:48:38,868 --> 04:48:37,560 okay so that concludes the first short 3980 04:48:41,690 --> 04:48:38,878 talk session so we're going to start our 3981 04:48:43,550 --> 04:48:41,700 poster session now be sure to find all 3982 04:48:45,230 --> 04:48:43,560 the speakers and others 3983 04:48:47,390 --> 04:48:45,240 um you know to talk to them at their 3984 04:48:49,788 --> 04:48:47,400 posters just a couple housekeeping 3985 04:48:51,670 --> 04:48:49,798 things our friends defense party is 3986 04:48:54,350 --> 04:48:51,680 happening in Surfside right now 3987 04:48:56,208 --> 04:48:54,360 so we've moved a lot of snacks and 3988 04:48:58,128 --> 04:48:56,218 coffee and all that just outside in the 3989 04:48:59,448 --> 04:48:58,138 courtyard so if you have a couple things 3990 04:49:01,670 --> 04:48:59,458 that you really need to grab from 3991 04:49:04,128 --> 04:49:01,680 Surfside just do it quickly and quietly 3992 04:49:05,510 --> 04:49:04,138 I think they're showing up at 1 30 but 3993 04:49:07,730 --> 04:49:05,520 for the next couple hours like really 3994 04:49:09,350 --> 04:49:07,740 we're just gonna be in the Forum we can 3995 04:49:11,090 --> 04:49:09,360 go outside on the green space but let's 3996 04:49:15,110 --> 04:49:11,100 just make sure that they can celebrate 3997 04:49:17,628 --> 04:49:15,120 and serve side and then one thing with 3998 04:49:20,330 --> 04:49:17,638 with trash we need to I guess we can't 3999 04:49:22,190 --> 04:49:20,340 put too much trash in there because I 4000 04:49:24,470 --> 04:49:22,200 guess UCSD catering usually takes care 4001 04:49:26,570 --> 04:49:24,480 of that so we've been told to just we'll 4002 04:49:28,610 --> 04:49:26,580 put out some other garbage cans but just 4003 04:49:29,628 --> 04:49:28,620 refrain from using those as much as 4004 04:49:34,060 --> 04:49:29,638 possible 4005 04:49:42,520 --> 04:49:34,070 uh yeah that's all thanks everyone 4006 04:50:22,690 --> 04:49:58,510 [Music] 4007 04:50:33,680 --> 04:50:22,700 thank you 4008 04:50:46,510 --> 04:50:44,690 [Music] 4009 04:50:59,860 --> 04:50:46,520 foreign 4010 04:51:22,500 --> 04:51:18,520 [Music] 4011 04:51:50,040 --> 04:51:22,510 thank you 4012 04:52:44,900 --> 04:51:55,730 [Music] 4013 04:52:56,100 --> 04:52:44,910 thank you 4014 04:53:10,050 --> 04:53:07,730 [Music] 4015 04:53:24,890 --> 04:53:10,060 foreign 4016 04:53:47,570 --> 04:53:39,120 [Music] 4017 04:54:26,390 --> 04:53:47,580 thank you 4018 04:54:29,390 --> 04:54:26,400 [Music] 4019 04:55:18,970 --> 04:54:29,400 foreign 4020 04:55:18,980 --> 04:55:31,710 thank you 4021 04:56:22,090 --> 04:55:36,830 [Music] 4022 04:56:22,100 --> 04:56:26,790 thank you 4023 04:56:56,448 --> 04:56:42,300 [Music] 4024 04:56:56,458 --> 04:57:01,130 foreign 4025 04:58:08,950 --> 04:57:23,220 [Music] 4026 04:58:21,700 --> 04:58:08,960 foreign 4027 04:58:57,610 --> 04:58:30,540 [Music] 4028 04:59:08,220 --> 04:58:59,350 thank you 4029 04:59:08,230 --> 04:59:34,730 [Music] 4030 04:59:34,740 --> 04:59:39,380 foreign 4031 05:00:15,420 --> 04:59:45,260 [Music] 4032 05:00:36,200 --> 05:00:15,430 thank you 4033 05:00:54,160 --> 05:00:47,020 [Music] 4034 05:01:14,640 --> 05:00:54,170 foreign 4035 05:02:06,830 --> 05:01:20,290 [Music] 4036 05:02:06,840 --> 05:02:21,180 foreign 4037 05:02:57,350 --> 05:02:33,050 [Music] 4038 05:03:09,140 --> 05:02:59,210 foreign 4039 05:04:04,208 --> 05:03:17,690 [Music] 4040 05:04:24,740 --> 05:04:06,930 thank you 4041 05:04:35,110 --> 05:04:30,390 [Music] 4042 05:04:35,120 --> 05:04:38,740 thank you 4043 05:04:38,750 --> 05:05:02,390 [Music] 4044 05:05:02,400 --> 05:05:17,670 foreign 4045 05:05:42,288 --> 05:05:33,650 [Music] 4046 05:06:04,680 --> 05:05:43,130 foreign 4047 05:06:04,690 --> 05:06:21,708 [Music] 4048 05:07:19,190 --> 05:06:23,740 foreign 4049 05:07:40,940 --> 05:07:36,640 [Music] 4050 05:07:54,140 --> 05:07:40,950 foreign 4051 05:07:54,150 --> 05:08:09,170 [Music] 4052 05:08:33,300 --> 05:08:11,550 foreign 4053 05:08:51,948 --> 05:08:46,490 [Music] 4054 05:09:02,870 --> 05:08:54,070 foreign 4055 05:09:02,880 --> 05:09:20,628 [Music] 4056 05:09:20,638 --> 05:09:25,700 foreign 4057 05:10:25,850 --> 05:09:42,660 [Music] 4058 05:10:25,860 --> 05:10:34,430 thank you 4059 05:10:48,660 --> 05:10:35,480 foreign 4060 05:11:14,590 --> 05:11:05,800 [Music] 4061 05:11:23,770 --> 05:11:14,600 thank you 4062 05:11:48,640 --> 05:11:36,740 [Music] 4063 05:12:02,780 --> 05:11:48,650 foreign 4064 05:12:30,890 --> 05:12:11,640 [Music] 4065 05:12:50,840 --> 05:12:33,390 foreign 4066 05:12:50,850 --> 05:13:03,470 [Music] 4067 05:13:03,480 --> 05:13:08,460 foreign 4068 05:13:53,990 --> 05:13:30,050 [Music] 4069 05:14:04,960 --> 05:13:56,290 foreign 4070 05:14:04,970 --> 05:14:15,590 [Music] 4071 05:14:34,490 --> 05:14:17,070 foreign 4072 05:14:34,500 --> 05:14:51,050 [Music] 4073 05:15:10,430 --> 05:14:53,020 foreign 4074 05:15:10,440 --> 05:15:27,230 [Music] 4075 05:15:45,380 --> 05:15:27,930 foreign 4076 05:16:07,170 --> 05:16:00,040 [Music] 4077 05:16:19,960 --> 05:16:07,180 thank you 4078 05:16:42,288 --> 05:16:32,380 [Music] 4079 05:17:00,060 --> 05:16:44,510 foreign 4080 05:17:00,070 --> 05:17:12,288 [Music] 4081 05:17:30,380 --> 05:17:14,830 foreign 4082 05:17:30,390 --> 05:17:38,990 [Music] 4083 05:17:39,000 --> 05:17:45,180 foreign 4084 05:17:45,190 --> 05:17:55,250 [Music] 4085 05:17:55,260 --> 05:18:00,090 foreign 4086 05:18:30,708 --> 05:18:15,460 [Music] 4087 05:18:39,810 --> 05:18:33,200 foreign 4088 05:19:10,120 --> 05:18:45,780 [Music] 4089 05:19:16,110 --> 05:19:10,130 foreign 4090 05:19:38,350 --> 05:19:33,720 [Music] 4091 05:19:46,400 --> 05:19:40,440 thank you 4092 05:19:46,410 --> 05:20:04,368 [Music] 4093 05:20:16,710 --> 05:20:05,680 foreign 4094 05:20:57,170 --> 05:20:24,410 [Music] 4095 05:21:17,340 --> 05:20:59,940 foreign 4096 05:21:30,340 --> 05:21:27,470 [Music] 4097 05:21:35,390 --> 05:21:30,350 foreign 4098 05:22:11,868 --> 05:21:35,400 [Music] 4099 05:22:11,878 --> 05:22:18,010 foreign 4100 05:23:20,090 --> 05:22:23,440 [Music] 4101 05:23:20,100 --> 05:23:23,420 foreign 4102 05:24:35,810 --> 05:23:36,250 [Music] 4103 05:24:49,600 --> 05:24:36,880 foreign 4104 05:25:07,220 --> 05:24:55,060 [Music] 4105 05:25:19,920 --> 05:25:07,230 foreign 4106 05:25:19,930 --> 05:25:24,890 [Music] 4107 05:25:24,900 --> 05:25:30,490 foreign 4108 05:25:55,250 --> 05:25:50,230 [Music] 4109 05:25:55,260 --> 05:26:00,800 foreign 4110 05:26:38,570 --> 05:26:20,550 [Music] 4111 05:26:41,060 --> 05:26:38,580 thank you 4112 05:26:50,860 --> 05:26:41,070 foreign 4113 05:27:55,430 --> 05:26:56,320 [Music] 4114 05:28:04,330 --> 05:27:56,930 foreign 4115 05:28:31,840 --> 05:28:21,810 [Music] 4116 05:28:46,560 --> 05:28:31,850 foreign 4117 05:29:17,650 --> 05:28:59,090 [Music] 4118 05:29:17,660 --> 05:29:22,090 thank you 4119 05:30:16,740 --> 05:29:45,110 [Music] 4120 05:30:22,550 --> 05:30:16,750 foreign 4121 05:31:17,330 --> 05:30:22,560 [Music] 4122 05:31:17,340 --> 05:31:21,400 foreign 4123 05:31:48,990 --> 05:31:30,530 [Music] 4124 05:32:18,070 --> 05:31:49,000 thank you 4125 05:32:19,070 --> 05:32:18,080 [Music] 4126 05:32:33,410 --> 05:32:19,080 thank you 4127 05:33:30,110 --> 05:32:33,420 [Music] 4128 05:34:10,310 --> 05:33:30,940 thank you 4129 05:34:38,000 --> 05:34:12,200 foreign 4130 05:35:12,708 --> 05:34:46,030 [Music] 4131 05:35:24,288 --> 05:35:14,720 foreign 4132 05:35:25,940 --> 05:35:24,298 [Music] 4133 05:35:59,708 --> 05:35:25,950 foreign 4134 05:36:34,208 --> 05:35:59,718 [Music] 4135 05:36:34,218 --> 05:36:40,650 thank you 4136 05:36:40,660 --> 05:36:45,730 [Music] 4137 05:36:45,740 --> 05:36:49,000 thank you 4138 05:37:24,550 --> 05:37:16,790 [Music] 4139 05:37:37,610 --> 05:37:26,060 thank you 4140 05:37:39,920 --> 05:37:37,620 [Music] 4141 05:37:49,610 --> 05:37:39,930 foreign 4142 05:37:51,410 --> 05:37:49,620 [Music] 4143 05:38:12,930 --> 05:37:51,420 foreign 4144 05:38:24,870 --> 05:38:21,890 [Music] 4145 05:39:03,910 --> 05:38:24,880 foreign 4146 05:39:07,570 --> 05:39:05,750 thank you 4147 05:39:48,490 --> 05:39:07,580 foreign 4148 05:39:48,500 --> 05:39:55,930 thank you 4149 05:39:55,940 --> 05:40:21,650 [Music] 4150 05:41:16,310 --> 05:40:23,180 foreign 4151 05:41:19,010 --> 05:41:16,320 [Music] 4152 05:41:28,430 --> 05:41:19,020 foreign 4153 05:41:30,540 --> 05:41:28,440 [Music] 4154 05:41:44,260 --> 05:41:30,550 foreign 4155 05:42:26,670 --> 05:41:58,720 [Music] 4156 05:42:40,190 --> 05:42:26,680 foreign 4157 05:42:40,800 --> 05:42:40,200 [Music] 4158 05:43:20,450 --> 05:42:40,810 foreign 4159 05:43:40,880 --> 05:43:38,930 [Music] 4160 05:43:53,628 --> 05:43:40,890 thank you 4161 05:43:55,010 --> 05:43:53,638 [Music] 4162 05:44:32,020 --> 05:43:55,020 foreign 4163 05:44:32,030 --> 05:44:58,010 [Music] 4164 05:45:07,730 --> 05:44:59,040 thank you 4165 05:45:09,940 --> 05:45:07,740 [Music] 4166 05:46:10,360 --> 05:45:09,950 foreign 4167 05:46:29,040 --> 05:46:26,510 [Music] 4168 05:47:27,530 --> 05:46:29,050 foreign 4169 05:47:29,740 --> 05:47:27,540 [Music] 4170 05:47:37,368 --> 05:47:29,750 thank you 4171 05:48:41,448 --> 05:47:37,378 [Music] 4172 05:48:46,070 --> 05:48:43,520 foreign 4173 05:48:46,470 --> 05:48:46,080 [Music] 4174 05:48:55,720 --> 05:48:46,480 foreign 4175 05:48:55,730 --> 05:49:39,650 [Music] 4176 05:49:53,960 --> 05:49:40,210 thank you 4177 05:51:04,730 --> 05:50:15,288 [Music] 4178 05:51:13,430 --> 05:51:06,270 thank you 4179 05:51:13,440 --> 05:51:24,530 [Music] 4180 05:51:24,540 --> 05:51:27,900 foreign 4181 05:52:13,910 --> 05:51:43,410 [Music] 4182 05:53:21,450 --> 05:52:13,920 foreign 4183 05:53:46,740 --> 05:53:44,690 [Music] 4184 05:53:49,010 --> 05:53:46,750 foreign 4185 05:53:51,870 --> 05:53:49,020 [Music] 4186 05:54:05,690 --> 05:53:51,880 foreign 4187 05:54:55,670 --> 05:54:18,410 [Music] 4188 05:55:17,650 --> 05:54:56,900 thank you 4189 05:55:17,660 --> 05:55:24,470 [Music] 4190 05:55:24,480 --> 05:55:32,790 thank you 4191 05:55:55,620 --> 05:55:45,790 [Music] 4192 05:56:25,070 --> 05:55:55,630 foreign 4193 05:57:26,990 --> 05:56:25,080 [Music] 4194 05:57:34,070 --> 05:57:27,000 foreign 4195 05:57:34,080 --> 05:57:51,890 [Music] 4196 05:57:51,900 --> 05:57:58,700 foreign 4197 05:59:04,700 --> 05:58:19,580 [Music] 4198 05:59:17,710 --> 05:59:04,710 foreign 4199 05:59:17,720 --> 05:59:29,570 [Music] 4200 05:59:29,580 --> 05:59:32,530 thank you 4201 05:59:59,550 --> 05:59:47,640 [Music] 4202 06:00:17,960 --> 05:59:59,560 foreign 4203 06:00:17,970 --> 06:00:30,490 [Music] 4204 06:00:48,280 --> 06:00:33,160 thank you 4205 06:00:48,290 --> 06:00:55,610 [Music] 4206 06:00:55,620 --> 06:01:01,440 foreign 4207 06:01:43,330 --> 06:01:11,340 [Music] 4208 06:01:43,340 --> 06:01:48,940 thank you 4209 06:02:50,810 --> 06:02:08,708 [Music] 4210 06:03:15,870 --> 06:02:52,860 foreign 4211 06:03:53,590 --> 06:03:27,570 [Music] 4212 06:04:02,390 --> 06:03:56,330 let's see 4213 06:04:08,160 --> 06:04:02,980 foreign 4214 06:04:32,740 --> 06:04:24,120 [Music] 4215 06:04:43,010 --> 06:04:32,750 foreign 4216 06:05:24,690 --> 06:04:50,810 [Music] 4217 06:05:45,170 --> 06:05:24,700 let's see 4218 06:06:23,030 --> 06:05:45,180 [Music] 4219 06:06:23,040 --> 06:06:29,010 foreign 4220 06:07:14,110 --> 06:06:30,948 [Music] 4221 06:07:26,740 --> 06:07:14,120 foreign 4222 06:07:49,900 --> 06:07:46,990 [Music] 4223 06:07:56,920 --> 06:07:49,910 thank you 4224 06:08:35,448 --> 06:08:05,850 [Music] 4225 06:08:53,150 --> 06:08:37,530 thank you 4226 06:08:53,160 --> 06:09:01,820 foreign 4227 06:09:49,780 --> 06:09:12,910 [Music] 4228 06:09:57,470 --> 06:09:49,790 foreign 4229 06:09:57,480 --> 06:10:03,590 [Music] 4230 06:10:03,600 --> 06:10:06,360 okay 4231 06:10:06,370 --> 06:10:16,990 [Music] 4232 06:10:17,000 --> 06:10:25,480 thank you 4233 06:11:08,940 --> 06:10:32,880 [Music] 4234 06:11:14,950 --> 06:11:08,950 thank you 4235 06:12:19,740 --> 06:11:16,850 [Music] 4236 06:13:00,880 --> 06:12:19,750 foreign 4237 06:13:00,890 --> 06:13:05,208 [Music] 4238 06:13:27,560 --> 06:13:07,010 foreign 4239 06:15:46,860 --> 06:13:46,340 [Music] 4240 06:16:02,450 --> 06:15:46,870 thank you 4241 06:17:40,208 --> 06:16:24,110 [Music] 4242 06:17:40,218 --> 06:17:47,030 thank you 4243 06:18:35,930 --> 06:18:12,230 [Music] 4244 06:18:57,670 --> 06:18:38,900 foreign 4245 06:18:57,680 --> 06:19:04,150 [Music] 4246 06:19:04,160 --> 06:19:10,460 thank you 4247 06:19:14,860 --> 06:19:13,510 [Music] 4248 06:19:30,010 --> 06:19:14,870 thank you 4249 06:19:56,048 --> 06:19:49,510 [Music] 4250 06:20:14,780 --> 06:19:57,540 thank you 4251 06:20:32,690 --> 06:20:22,700 [Music] 4252 06:20:32,700 --> 06:20:36,370 foreign 4253 06:21:07,350 --> 06:20:48,630 [Music] 4254 06:21:13,790 --> 06:21:07,360 foreign 4255 06:21:13,800 --> 06:21:20,708 [Music] 4256 06:21:20,718 --> 06:21:24,590 thank you 4257 06:21:24,600 --> 06:21:50,570 [Music] 4258 06:21:50,580 --> 06:21:54,210 foreign 4259 06:22:42,420 --> 06:22:06,480 [Music] 4260 06:22:58,360 --> 06:22:42,430 thank you 4261 06:22:58,370 --> 06:23:17,890 [Music] 4262 06:23:17,900 --> 06:23:23,570 thank you 4263 06:24:33,850 --> 06:23:50,270 [Music] 4264 06:24:41,360 --> 06:24:34,910 thank you 4265 06:25:18,090 --> 06:25:15,368 [Music] 4266 06:25:34,060 --> 06:25:18,100 thank you 4267 06:25:34,070 --> 06:25:40,570 [Music] 4268 06:25:40,580 --> 06:25:44,210 thank you 4269 06:26:10,010 --> 06:25:56,200 [Music] 4270 06:26:19,220 --> 06:26:16,430 foreign 4271 06:26:19,230 --> 06:27:04,750 [Music] 4272 06:27:04,760 --> 06:27:09,860 thank you 4273 06:27:38,708 --> 06:27:26,560 [Music] 4274 06:27:38,718 --> 06:27:43,220 thank you 4275 06:27:43,230 --> 06:27:58,368 [Music] 4276 06:28:11,570 --> 06:28:01,100 foreign 4277 06:29:08,510 --> 06:28:18,820 [Music] 4278 06:29:50,990 --> 06:29:09,870 foreign 4279 06:30:34,788 --> 06:29:53,930 [Music] 4280 06:30:34,798 --> 06:30:42,550 foreign 4281 06:31:06,048 --> 06:30:50,020 [Music] 4282 06:31:14,470 --> 06:31:07,890 foreign 4283 06:31:35,510 --> 06:31:23,630 [Music] 4284 06:31:54,840 --> 06:31:38,140 foreign 4285 06:32:04,010 --> 06:32:03,410 [Music] 4286 06:32:14,460 --> 06:32:04,020 thank you 4287 06:33:30,948 --> 06:32:18,650 [Music] 4288 06:33:30,958 --> 06:33:33,820 foreign 4289 06:34:10,128 --> 06:33:44,410 [Music] 4290 06:34:10,138 --> 06:34:19,740 foreign 4291 06:34:40,610 --> 06:34:37,620 [Music] 4292 06:35:01,240 --> 06:34:40,620 foreign 4293 06:35:25,430 --> 06:35:16,160 [Music] 4294 06:35:25,440 --> 06:35:41,610 thank you 4295 06:35:59,030 --> 06:35:50,770 [Music] 4296 06:35:59,040 --> 06:36:06,270 foreign 4297 06:37:15,288 --> 06:36:16,480 [Music] 4298 06:37:30,780 --> 06:37:18,260 foreign 4299 06:39:39,830 --> 06:37:44,570 [Music] 4300 06:39:48,100 --> 06:39:39,840 foreign 4301 06:40:52,430 --> 06:39:59,880 [Music] 4302 06:41:17,390 --> 06:40:53,800 foreign 4303 06:41:36,590 --> 06:41:32,140 [Music] 4304 06:41:36,600 --> 06:41:41,080 thank you 4305 06:42:00,650 --> 06:41:49,750 [Music] 4306 06:42:09,490 --> 06:42:01,240 thank you 4307 06:42:41,720 --> 06:42:38,240 [Music] 4308 06:42:58,440 --> 06:42:41,730 thank you 4309 06:43:49,250 --> 06:43:12,660 [Music] 4310 06:44:03,570 --> 06:43:50,540 foreign 4311 06:44:03,580 --> 06:44:26,990 [Music] 4312 06:44:30,110 --> 06:44:28,430 foreign 4313 06:44:33,708 --> 06:44:30,120 [Music] 4314 06:44:35,330 --> 06:44:33,718 everybody we're gonna start our salty 4315 06:44:37,010 --> 06:44:35,340 stuff talk session the last one of the 4316 06:44:40,210 --> 06:44:37,020 day and our first speaker will be Emily 4317 06:44:45,110 --> 06:44:40,220 Paris from Stanford University 4318 06:44:48,350 --> 06:44:45,120 [Applause] 4319 06:44:50,150 --> 06:44:48,360 hi everyone I'm Emily and I'm a PhD 4320 06:44:52,490 --> 06:44:50,160 candidate in the dica slab at Stanford 4321 06:44:56,030 --> 06:44:52,500 University and I studied the limits of 4322 06:44:58,368 --> 06:44:56,040 life in hyper saline environments 4323 06:44:59,868 --> 06:44:58,378 so as we all probably know Brian's are 4324 06:45:02,090 --> 06:44:59,878 one of the targets for a life detection 4325 06:45:04,548 --> 06:45:02,100 mission to other ocean worlds including 4326 06:45:07,310 --> 06:45:04,558 Europa and Enceladus and even past ocean 4327 06:45:10,010 --> 06:45:07,320 worlds like Mars and so by understanding 4328 06:45:12,350 --> 06:45:10,020 the limits of salty life on Earth we can 4329 06:45:15,410 --> 06:45:12,360 understand how and where to look for 4330 06:45:17,448 --> 06:45:15,420 life on these other places 4331 06:45:18,948 --> 06:45:17,458 one of the ways we can assess a brine 4332 06:45:21,590 --> 06:45:18,958 environment is through this measurement 4333 06:45:23,330 --> 06:45:21,600 called water activity and water activity 4334 06:45:25,430 --> 06:45:23,340 depends on vapor pressure but you can 4335 06:45:27,650 --> 06:45:25,440 think of it about as how many water 4336 06:45:30,048 --> 06:45:27,660 molecules are available to a cell in 4337 06:45:31,730 --> 06:45:30,058 solution so on the left is an image of 4338 06:45:33,830 --> 06:45:31,740 what pure water would be this is where 4339 06:45:35,810 --> 06:45:33,840 all the water molecules are free to 4340 06:45:38,270 --> 06:45:35,820 become Vapor move about the cabin that 4341 06:45:40,910 --> 06:45:38,280 would be a water activity of one 4342 06:45:42,830 --> 06:45:40,920 now if there's ions in solution water 4343 06:45:45,170 --> 06:45:42,840 would be attracted to those molecules 4344 06:45:46,930 --> 06:45:45,180 and a water activity would decrease so 4345 06:45:49,730 --> 06:45:46,940 the lower the water activity the more 4346 06:45:51,708 --> 06:45:49,740 uninhabitable an environment is 4347 06:45:53,868 --> 06:45:51,718 and since water is required for all Life 4348 06:45:57,048 --> 06:45:53,878 as We Know It water activity can be used 4349 06:45:59,390 --> 06:45:57,058 to assess assess habitability so some 4350 06:46:01,128 --> 06:45:59,400 common items in their water activities 4351 06:46:02,390 --> 06:46:01,138 are listed on the left including sea 4352 06:46:04,548 --> 06:46:02,400 water which has a pretty high water 4353 06:46:06,470 --> 06:46:04,558 activity and the salinity of seawater is 4354 06:46:08,270 --> 06:46:06,480 about 3.5 percent 4355 06:46:10,730 --> 06:46:08,280 and then honey has a water activity of 4356 06:46:13,190 --> 06:46:10,740 0.6 and some of Mars special regions or 4357 06:46:16,548 --> 06:46:13,200 areas where we might detect life on Mars 4358 06:46:20,510 --> 06:46:18,170 and there's been a lot of really great 4359 06:46:23,150 --> 06:46:20,520 pure culture work on the limits of life 4360 06:46:25,490 --> 06:46:23,160 and cell division at different water 4361 06:46:27,530 --> 06:46:25,500 activities and to sum it up the 4362 06:46:29,390 --> 06:46:27,540 predicted or theoretical water activity 4363 06:46:31,850 --> 06:46:29,400 limit for all life on Earth including 4364 06:46:34,190 --> 06:46:31,860 eukaryotes and prokaryotes is about 0.6 4365 06:46:36,410 --> 06:46:34,200 and this is based on pure culture so 4366 06:46:38,208 --> 06:46:36,420 like our speaker last night mentioned 4367 06:46:40,190 --> 06:46:38,218 not all the things in the world are in 4368 06:46:42,708 --> 06:46:40,200 pure culture yet so that leaves out 4369 06:46:45,048 --> 06:46:42,718 about 90 or more of the biodiversity on 4370 06:46:46,490 --> 06:46:45,058 Earth and our ability to assess what the 4371 06:46:50,390 --> 06:46:46,500 limit of life for each of those strains 4372 06:46:54,350 --> 06:46:52,070 so brine environments are really 4373 06:46:56,990 --> 06:46:54,360 widespread on Earth they're everywhere 4374 06:46:59,330 --> 06:46:57,000 um and a lot of great work has gone into 4375 06:47:01,070 --> 06:46:59,340 assessing metagenomics like the 4376 06:47:02,750 --> 06:47:01,080 taxonomic diversity the potential 4377 06:47:04,868 --> 06:47:02,760 metabolic metabolic potential of 4378 06:47:06,830 --> 06:47:04,878 microbes in these environments 4379 06:47:08,810 --> 06:47:06,840 metatranscriptomes and even some bulk 4380 06:47:10,490 --> 06:47:08,820 activity measurements but metabolic 4381 06:47:11,810 --> 06:47:10,500 activity is rarely measured at the 4382 06:47:13,490 --> 06:47:11,820 Single Cell level 4383 06:47:15,708 --> 06:47:13,500 and this can be really important because 4384 06:47:17,510 --> 06:47:15,718 when a cell is stressed out they might 4385 06:47:19,910 --> 06:47:17,520 have really low levels of activity that 4386 06:47:21,410 --> 06:47:19,920 are not detected with bulk techniques 4387 06:47:23,510 --> 06:47:21,420 so today I'll be talking a little bit 4388 06:47:25,310 --> 06:47:23,520 about my work in solar cell turns and 4389 06:47:29,448 --> 06:47:25,320 then transition into the my current work 4390 06:47:32,150 --> 06:47:29,458 in Western Australia aesthetic brands 4391 06:47:34,548 --> 06:47:32,160 so like I mentioned when life is 4392 06:47:36,830 --> 06:47:34,558 reaching its limit a metabolic activity 4393 06:47:38,868 --> 06:47:36,840 can be really low and so single cell 4394 06:47:41,150 --> 06:47:38,878 analysis can help us detect the slow 4395 06:47:44,570 --> 06:47:41,160 level of activity by lowering detection 4396 06:47:46,548 --> 06:47:44,580 limits so a cell needs to acquire 50 new 4397 06:47:49,010 --> 06:47:46,558 biomass to be able to divide into two 4398 06:47:51,230 --> 06:47:49,020 new daughter cells however with Nano 4399 06:47:53,628 --> 06:47:51,240 Sims for example we only need to detect 4400 06:47:56,090 --> 06:47:53,638 about five percent maximum we can even 4401 06:47:58,310 --> 06:47:56,100 get as low as less than one percent of 4402 06:48:00,708 --> 06:47:58,320 new biomass to detect active life in a 4403 06:48:02,448 --> 06:48:00,718 sample it also provides quantitative 4404 06:48:04,730 --> 06:48:02,458 results so we can do a law with this 4405 06:48:06,590 --> 06:48:04,740 data on a quantitative level and it also 4406 06:48:09,048 --> 06:48:06,600 reveals trends that are often obscured 4407 06:48:10,788 --> 06:48:09,058 by bulk analysis 4408 06:48:12,170 --> 06:48:10,798 and when I'm talking about metabolic 4409 06:48:14,750 --> 06:48:12,180 activity in this talk I'm talking 4410 06:48:16,548 --> 06:48:14,760 specifically about anabolic activity so 4411 06:48:18,170 --> 06:48:16,558 there's catabolic activity that produces 4412 06:48:20,270 --> 06:48:18,180 energy for a cell and then there's 4413 06:48:22,128 --> 06:48:20,280 anabolic activity where a cell can take 4414 06:48:24,468 --> 06:48:22,138 substrates from the environment like 4415 06:48:26,510 --> 06:48:24,478 amino acids and glucose and take that 4416 06:48:29,510 --> 06:48:26,520 carbon and nitrogen and then produce new 4417 06:48:32,990 --> 06:48:29,520 cell biomass which includes proteins DNA 4418 06:48:36,770 --> 06:48:34,850 so first the work that I've done at this 4419 06:48:39,770 --> 06:48:36,780 solar Sultan it's called South Bay 4420 06:48:41,750 --> 06:48:39,780 saltworks it's in here in San Diego and 4421 06:48:43,788 --> 06:48:41,760 basically they bring sea water in from 4422 06:48:46,190 --> 06:48:43,798 San Diego Bay and it goes through a 4423 06:48:47,990 --> 06:48:46,200 series of evapo concentration ponds and 4424 06:48:49,788 --> 06:48:48,000 as the water evaporates out of the sea 4425 06:48:51,890 --> 06:48:49,798 water different salts are left behind 4426 06:48:54,530 --> 06:48:51,900 producing a series of ponds that range 4427 06:48:56,570 --> 06:48:54,540 in water activity from 0.98 that of 4428 06:48:58,610 --> 06:48:56,580 seawater to that well below the known 4429 06:49:01,128 --> 06:48:58,620 limit of Life at 0.4 4430 06:49:03,708 --> 06:49:01,138 and so we measured anabolic activity of 4431 06:49:06,048 --> 06:49:03,718 over 6 000 individual cells from a 4432 06:49:08,448 --> 06:49:06,058 series of five of these brines with five 4433 06:49:10,368 --> 06:49:08,458 different isotopic substrates from amino 4434 06:49:13,128 --> 06:49:10,378 acids ammonium and bicarbonate glucose 4435 06:49:15,468 --> 06:49:13,138 and nitrate and that sort of thing 4436 06:49:17,208 --> 06:49:15,478 we measured their anabolic activity with 4437 06:49:19,610 --> 06:49:17,218 nano SIM so on the left this is what 4438 06:49:21,350 --> 06:49:19,620 this looks like cells that are circled 4439 06:49:24,110 --> 06:49:21,360 in red are considered enriched and this 4440 06:49:25,730 --> 06:49:24,120 is for carbon from amino acids and then 4441 06:49:27,770 --> 06:49:25,740 the cells that are circled in white 4442 06:49:30,230 --> 06:49:27,780 would be considered less active or less 4443 06:49:31,670 --> 06:49:30,240 enriched in the sample 4444 06:49:34,190 --> 06:49:31,680 and when you plot this with water 4445 06:49:36,288 --> 06:49:34,200 activity you see that microbial activity 4446 06:49:38,690 --> 06:49:36,298 decreases exponentially with water 4447 06:49:40,730 --> 06:49:38,700 activity however there are certain areas 4448 06:49:42,770 --> 06:49:40,740 so can we see this yeah 4449 06:49:44,810 --> 06:49:42,780 yeah certain subsets of cells are more 4450 06:49:47,270 --> 06:49:44,820 active than most of the cells in 4451 06:49:49,128 --> 06:49:47,280 seawater at a higher water activity with 4452 06:49:50,150 --> 06:49:49,138 even just low decreases in water 4453 06:49:52,850 --> 06:49:50,160 activity 4454 06:49:55,250 --> 06:49:52,860 we also detected cell biomass through 4455 06:49:57,110 --> 06:49:55,260 dappy and nanosims in this low water 4456 06:49:59,090 --> 06:49:57,120 activity magnesium chloride brine 4457 06:50:01,490 --> 06:49:59,100 however we didn't detect any activity 4458 06:50:03,230 --> 06:50:01,500 here and the incubation time was two 4459 06:50:05,090 --> 06:50:03,240 days long so there's several reasons for 4460 06:50:10,968 --> 06:50:05,100 this 4461 06:50:13,548 --> 06:50:10,978 estimate a new predicted lower limit of 4462 06:50:15,530 --> 06:50:13,558 Life at 0.54 so that's a little 4463 06:50:17,750 --> 06:50:15,540 significantly biologically significantly 4464 06:50:21,530 --> 06:50:17,760 lower than the 0.6 previous limit 4465 06:50:23,090 --> 06:50:21,540 detected sorry predicted and this data 4466 06:50:24,590 --> 06:50:23,100 I'd love to talk more about it but it's 4467 06:50:25,968 --> 06:50:24,600 been submitted and I just got word that 4468 06:50:27,830 --> 06:50:25,978 it's now in review the as of this 4469 06:50:28,730 --> 06:50:27,840 morning so it's really exciting and if 4470 06:50:31,070 --> 06:50:28,740 you'd like to hear more about that 4471 06:50:33,048 --> 06:50:31,080 please talk to me later 4472 06:50:35,090 --> 06:50:33,058 so now to kind of get into the topic of 4473 06:50:36,650 --> 06:50:35,100 this talk which is I'm talking about the 4474 06:50:38,810 --> 06:50:36,660 limits of life in acidic brine 4475 06:50:41,690 --> 06:50:38,820 environments there's a lot of things 4476 06:50:43,670 --> 06:50:41,700 that happen in brines so you can have 4477 06:50:45,708 --> 06:50:43,680 salinity as a limiting factor you can 4478 06:50:46,788 --> 06:50:45,718 have high metal concentrations you can 4479 06:50:48,830 --> 06:50:46,798 have high ionic strength and 4480 06:50:50,750 --> 06:50:48,840 chaotropicity but one thing that really 4481 06:50:52,670 --> 06:50:50,760 stood out to me about this sample set 4482 06:50:54,890 --> 06:50:52,680 was that most of the brines that had 4483 06:50:56,690 --> 06:50:54,900 high levels of activity actually had a 4484 06:50:58,750 --> 06:50:56,700 pH about seven or eight so like 4485 06:51:01,490 --> 06:50:58,760 relatively neutral to slightly basic pH 4486 06:51:04,250 --> 06:51:01,500 however this magnesium chloride brine 4487 06:51:06,708 --> 06:51:04,260 which had no detectable activity had a 4488 06:51:08,750 --> 06:51:06,718 pH of about 5.4 4489 06:51:11,090 --> 06:51:08,760 and so my question was how does pH 4490 06:51:12,708 --> 06:51:11,100 affect microbial activity in brine 4491 06:51:13,850 --> 06:51:12,718 environments and is this an important 4492 06:51:16,850 --> 06:51:13,860 factor 4493 06:51:19,490 --> 06:51:16,860 in the limits of life 4494 06:51:21,770 --> 06:51:19,500 so last summer our team went to Western 4495 06:51:24,530 --> 06:51:21,780 Australia to sample a bunch of acidic 4496 06:51:26,628 --> 06:51:24,540 brines and these brines are considered 4497 06:51:28,548 --> 06:51:26,638 Mars analogs because of the geochemistry 4498 06:51:30,890 --> 06:51:28,558 and weathering systems that created them 4499 06:51:33,770 --> 06:51:30,900 over millions of years 4500 06:51:35,628 --> 06:51:33,780 um just in short oxidation of sulfides 4501 06:51:37,968 --> 06:51:35,638 acidified the water and then evaporation 4502 06:51:40,128 --> 06:51:37,978 concentrated ions and other salts over 4503 06:51:42,410 --> 06:51:40,138 time creating these really acidic Briny 4504 06:51:43,730 --> 06:51:42,420 environments 4505 06:51:45,530 --> 06:51:43,740 um there's hundreds of these lakes and 4506 06:51:48,350 --> 06:51:45,540 we were really lucky to sample a really 4507 06:51:50,510 --> 06:51:48,360 broad spectrum of them so on the x-axis 4508 06:51:53,390 --> 06:51:50,520 is water activity and on the y-axis is 4509 06:51:56,030 --> 06:51:53,400 pH and I was really thrilled to get a 4510 06:51:58,490 --> 06:51:56,040 nice group of lakes to sample for 4511 06:52:00,890 --> 06:51:58,500 activity analysis especially these ones 4512 06:52:03,830 --> 06:52:00,900 that are boxed these are were at a water 4513 06:52:05,930 --> 06:52:03,840 activity of 0.7 and they range in PH so 4514 06:52:08,410 --> 06:52:05,940 it's a really good opportunity to kind 4515 06:52:11,750 --> 06:52:08,420 of look at how pH affects my metabolism 4516 06:52:15,948 --> 06:52:11,760 at low water activity 4517 06:52:18,110 --> 06:52:15,958 so with this uh this study I analyzed 4518 06:52:20,750 --> 06:52:18,120 metabolic activity specifically anabolic 4519 06:52:23,628 --> 06:52:20,760 activity by incubating these brines with 4520 06:52:25,850 --> 06:52:23,638 an analog amino acid called hpg 4521 06:52:28,010 --> 06:52:25,860 cells that are active in the sample will 4522 06:52:30,410 --> 06:52:28,020 take up hpg and incorporate them into 4523 06:52:33,350 --> 06:52:30,420 their new proteins that are produced and 4524 06:52:35,448 --> 06:52:33,360 then the hpg has a alkyne group on the 4525 06:52:37,368 --> 06:52:35,458 end that later on in lab you can perform 4526 06:52:39,410 --> 06:52:37,378 click chemistry on and click a four or 4527 06:52:41,150 --> 06:52:39,420 four to it so all the cells that are 4528 06:52:43,070 --> 06:52:41,160 active in the sample turn out green 4529 06:52:45,048 --> 06:52:43,080 under the microscope or in flow 4530 06:52:47,150 --> 06:52:45,058 cytometry and then that can be 4531 06:52:49,190 --> 06:52:47,160 counter-stained or compared to cells 4532 06:52:51,230 --> 06:52:49,200 that are stained blue via DNA stain of 4533 06:52:53,030 --> 06:52:51,240 doping and so with this data you can 4534 06:52:55,730 --> 06:52:53,040 calculate the percent of active cells 4535 06:52:57,650 --> 06:52:55,740 across these Lakes 4536 06:52:59,090 --> 06:52:57,660 so this is just an example of what this 4537 06:53:01,070 --> 06:52:59,100 data set looks like these are just four 4538 06:53:03,170 --> 06:53:01,080 of the 13 or 14 lakes that we were able 4539 06:53:05,930 --> 06:53:03,180 to do this with on the left the lakes 4540 06:53:07,190 --> 06:53:05,940 are ordered and decreasing pH and I 4541 06:53:09,110 --> 06:53:07,200 thought it was also kind of interesting 4542 06:53:10,430 --> 06:53:09,120 the color changes so you can admire 4543 06:53:12,288 --> 06:53:10,440 those I don't know why they do that but 4544 06:53:14,208 --> 06:53:12,298 that's the way it is and then in the 4545 06:53:16,490 --> 06:53:14,218 middle are the dappy stain cells under 4546 06:53:18,170 --> 06:53:16,500 the microscope and then on the right are 4547 06:53:20,390 --> 06:53:18,180 the active cells that are tagged with 4548 06:53:22,548 --> 06:53:20,400 the green fluorophore 4549 06:53:24,650 --> 06:53:22,558 you can also notice like the different 4550 06:53:26,510 --> 06:53:24,660 cell morphologies and abundances that 4551 06:53:29,510 --> 06:53:26,520 change with ph which is really 4552 06:53:32,090 --> 06:53:29,520 fascinating and also that pH didn't 4553 06:53:34,548 --> 06:53:32,100 affect the assay itself we do see some 4554 06:53:36,230 --> 06:53:34,558 cells that are active at these low ph's 4555 06:53:40,670 --> 06:53:36,240 and sometimes you have Brands where 4556 06:53:43,670 --> 06:53:42,170 so when you calculate the percent of 4557 06:53:45,890 --> 06:53:43,680 active cells and you put this all in a 4558 06:53:47,810 --> 06:53:45,900 plot I'll just Orient you so on the 4559 06:53:50,930 --> 06:53:47,820 x-axis here we have water activity 4560 06:53:52,788 --> 06:53:50,940 decreasing and on the y-axis is pH 4561 06:53:55,190 --> 06:53:52,798 decreasing in this direction so you 4562 06:53:58,490 --> 06:53:55,200 would expect the most extreme acidic 4563 06:54:00,288 --> 06:53:58,500 brines to be kind of in this region 4564 06:54:02,150 --> 06:54:00,298 um this dotted line is that newly 4565 06:54:04,070 --> 06:54:02,160 predicted water activity limit of life 4566 06:54:05,868 --> 06:54:04,080 that I talked about earlier and then 4567 06:54:08,930 --> 06:54:05,878 this dotted line represents the percent 4568 06:54:11,390 --> 06:54:08,940 of active cells dropping below 50 at 4569 06:54:13,910 --> 06:54:11,400 this pH so this color block each of the 4570 06:54:15,530 --> 06:54:13,920 dots is one Lake and the color bar was 4571 06:54:18,410 --> 06:54:15,540 colored on a green gradient if the 4572 06:54:20,208 --> 06:54:18,420 percent of active cells is above 50 and 4573 06:54:22,310 --> 06:54:20,218 on a gradient towards black if it was 4574 06:54:25,190 --> 06:54:22,320 below 50 so you can kind of just 4575 06:54:27,048 --> 06:54:25,200 visually see that all of the green like 4576 06:54:29,330 --> 06:54:27,058 high percentage act cells cluster up 4577 06:54:31,128 --> 06:54:29,340 here and all of the low percent of 4578 06:54:32,628 --> 06:54:31,138 active cells cluster down here 4579 06:54:34,250 --> 06:54:32,638 and when you look at it statistically 4580 06:54:36,230 --> 06:54:34,260 there is a moderately stronger 4581 06:54:38,468 --> 06:54:36,240 correlation with ph and activity 4582 06:54:40,788 --> 06:54:38,478 compared to water activity and activity 4583 06:54:43,850 --> 06:54:40,798 so so many times you can count how many 4584 06:54:46,430 --> 06:54:43,860 times I say activity in this talk 4585 06:54:49,190 --> 06:54:46,440 um and so some thoughts on this 4586 06:54:51,468 --> 06:54:49,200 a pH of six is really high for 4587 06:54:52,850 --> 06:54:51,478 environmental samples and as we've heard 4588 06:54:55,548 --> 06:54:52,860 from a lot of people and as we know 4589 06:54:57,530 --> 06:54:55,558 there's a lot of microbes that live in 4590 06:54:59,930 --> 06:54:57,540 way more acidic environments so what's 4591 06:55:01,788 --> 06:54:59,940 actually happening here I don't have an 4592 06:55:03,590 --> 06:55:01,798 answer to that yet and I'm hoping to 4593 06:55:05,628 --> 06:55:03,600 figure that out with future analyzes 4594 06:55:07,368 --> 06:55:05,638 that include nanosims work on these 4595 06:55:10,010 --> 06:55:07,378 Lakes 4596 06:55:11,690 --> 06:55:10,020 um and then if this is a true signal and 4597 06:55:14,810 --> 06:55:11,700 this is what what is going on in the 4598 06:55:16,788 --> 06:55:14,820 environment then microbial activity may 4599 06:55:20,270 --> 06:55:16,798 be detected at lower water activities 4600 06:55:22,368 --> 06:55:20,280 than we know of now as long as the pH is 4601 06:55:24,048 --> 06:55:22,378 within the seven to eight maybe like not 4602 06:55:25,910 --> 06:55:24,058 so acidic range 4603 06:55:27,468 --> 06:55:25,920 um so figuring out what that PH range is 4604 06:55:29,390 --> 06:55:27,478 and how that interacts with water 4605 06:55:33,708 --> 06:55:29,400 activity limits of life 4606 06:55:38,868 --> 06:55:36,590 so with that I'd like to acknowledge my 4607 06:55:41,510 --> 06:55:38,878 lab the DECA slab pictured up in the 4608 06:55:43,310 --> 06:55:41,520 rights all of our funding sources the 4609 06:55:44,868 --> 06:55:43,320 oceans across space and time team which 4610 06:55:46,850 --> 06:55:44,878 is a nasa-funded project you'll hear 4611 06:55:49,430 --> 06:55:46,860 about uh you'll hear from a lot of us 4612 06:55:50,990 --> 06:55:49,440 throughout this conference and all of 4613 06:55:53,270 --> 06:55:51,000 our collaborators in Western Australia 4614 06:55:54,590 --> 06:55:53,280 including Molly the dingo who of course 4615 06:55:56,810 --> 06:55:54,600 this work would not have been possible 4616 06:55:59,208 --> 06:55:57,948 all right and then I'll take any 4617 06:56:00,890 --> 06:55:59,218 questions and I'll leave this up so you 4618 06:56:02,400 --> 06:56:00,900 can stare at the dots for a little bit 4619 06:56:09,590 --> 06:56:02,410 longer 4620 06:56:22,670 --> 06:56:09,600 [Applause] 4621 06:56:26,390 --> 06:56:25,128 hi uh that was really cool talk thanks 4622 06:56:27,890 --> 06:56:26,400 so much 4623 06:56:30,048 --> 06:56:27,900 um I was just wondering if he could 4624 06:56:33,468 --> 06:56:30,058 expand a little bit on why you 4625 06:56:35,570 --> 06:56:33,478 concentrate onion anabolic 4626 06:56:36,590 --> 06:56:35,580 um activity as opposed to catabolic 4627 06:56:38,930 --> 06:56:36,600 activity 4628 06:56:42,110 --> 06:56:38,940 yeah so 4629 06:56:44,150 --> 06:56:42,120 let's see scientifically the reason why 4630 06:56:45,770 --> 06:56:44,160 I would focus on anabolic activity I 4631 06:56:47,448 --> 06:56:45,780 mean both catabolic and anabolic 4632 06:56:51,288 --> 06:56:47,458 activity are essential for life right 4633 06:56:53,270 --> 06:56:51,298 life has to make energy to assimilate 4634 06:56:55,510 --> 06:56:53,280 substrates and ground divides so both 4635 06:56:58,190 --> 06:56:55,520 processes are really important 4636 06:57:00,650 --> 06:56:58,200 and they are processes that I'll be 4637 06:57:02,690 --> 06:57:00,660 combining or looking at in future field 4638 06:57:04,730 --> 06:57:02,700 sites 4639 06:57:06,770 --> 06:57:04,740 um with anabolic activity the 4640 06:57:08,208 --> 06:57:06,780 interesting thing here is that you could 4641 06:57:10,548 --> 06:57:08,218 imagine that when a cell gets really 4642 06:57:13,070 --> 06:57:10,558 stressed out it would stop dividing 4643 06:57:16,010 --> 06:57:13,080 potentially and still accumulate 4644 06:57:18,170 --> 06:57:16,020 substrates to repair DNA repair cell 4645 06:57:20,810 --> 06:57:18,180 walls do all that stuff until conditions 4646 06:57:23,930 --> 06:57:20,820 get better and so the idea was that or 4647 06:57:26,270 --> 06:57:23,940 my original hypothesis was that by 4648 06:57:28,490 --> 06:57:26,280 um that anabolic activity would extend 4649 06:57:33,110 --> 06:57:28,500 beyond the known cell division limit of 4650 06:57:34,610 --> 06:57:33,120 life because even as cells are um cells 4651 06:57:36,350 --> 06:57:34,620 would be able to survive just by taking 4652 06:57:38,030 --> 06:57:36,360 up materials and so that taking up 4653 06:57:47,330 --> 06:57:38,040 process is the anabolic Activity Part 4654 06:57:53,270 --> 06:57:48,890 sweet talk 4655 06:57:56,530 --> 06:57:53,280 I have a question so um you mentioned 4656 06:58:00,288 --> 06:57:56,540 that you guys have essentially like uh 4657 06:58:02,628 --> 06:58:00,298 extrapolated uh new 4658 06:58:04,850 --> 06:58:02,638 like limit for life like in terms of 4659 06:58:08,330 --> 06:58:04,860 water activity it's kind of a power move 4660 06:58:11,090 --> 06:58:08,340 so we're not the first ones to do this 4661 06:58:13,010 --> 06:58:11,100 okay but okay but uh could you explain 4662 06:58:14,448 --> 06:58:13,020 how you extrapolated that because I 4663 06:58:16,310 --> 06:58:14,458 think maybe I missed that or I didn't 4664 06:58:17,750 --> 06:58:16,320 understand yeah um okay we're gonna get 4665 06:58:19,548 --> 06:58:17,760 into the weeds here but let me go back 4666 06:58:22,190 --> 06:58:19,558 to that slide 4667 06:58:25,070 --> 06:58:22,200 um so this this idea or this like 4668 06:58:26,288 --> 06:58:25,080 extrapolation is based on 4669 06:58:29,208 --> 06:58:26,298 um 4670 06:58:30,590 --> 06:58:29,218 these this study here so they did the 4671 06:58:32,510 --> 06:58:30,600 same thing and this is how they got this 4672 06:58:34,548 --> 06:58:32,520 theoretical limit of life that has now 4673 06:58:36,410 --> 06:58:34,558 been cited almost 200 times from food 4674 06:58:38,150 --> 06:58:36,420 preservation fields to life detection 4675 06:58:40,030 --> 06:58:38,160 Fields so 4676 06:58:43,490 --> 06:58:40,040 um 4677 06:58:44,990 --> 06:58:43,500 hasn't been published yet 4678 06:58:46,548 --> 06:58:45,000 um so the reason so they used a 4679 06:58:49,490 --> 06:58:46,558 different technique and they based it on 4680 06:58:50,990 --> 06:58:49,500 cell division and so we're 4681 06:58:52,250 --> 06:58:51,000 um 4682 06:58:53,628 --> 06:58:52,260 so hang on let me answer your first 4683 06:58:55,128 --> 06:58:53,638 question so 4684 06:58:57,830 --> 06:58:55,138 um the way that we did this is single 4685 06:58:59,090 --> 06:58:57,840 cell analysis allows you to separate the 4686 06:59:01,070 --> 06:58:59,100 cells that are active from those that 4687 06:59:02,810 --> 06:59:01,080 are inactive and in a brine environment 4688 06:59:04,910 --> 06:59:02,820 this is really important because brines 4689 06:59:07,190 --> 06:59:04,920 are really salty and cells can fall in 4690 06:59:09,350 --> 06:59:07,200 from anywhere bird poop wind whatever 4691 06:59:11,208 --> 06:59:09,360 and get preserved and those can be 4692 06:59:13,910 --> 06:59:11,218 inactive so those can contribute to that 4693 06:59:16,368 --> 06:59:13,920 bulk analysis and not necessarily even 4694 06:59:17,990 --> 06:59:16,378 be important in that environment so a 4695 06:59:20,030 --> 06:59:18,000 single cell analysis we took out the 4696 06:59:21,530 --> 06:59:20,040 active cells average their anabolic 4697 06:59:24,230 --> 06:59:21,540 activities so we're just focusing on 4698 06:59:26,990 --> 06:59:24,240 who's contributing to metabolism in that 4699 06:59:30,410 --> 06:59:27,000 environment and then use detection 4700 06:59:32,690 --> 06:59:30,420 limits and and math to extrapolate and 4701 06:59:35,390 --> 06:59:32,700 predict or propose this new predicted 4702 06:59:37,430 --> 06:59:35,400 limit of detectable life and so this is 4703 06:59:39,468 --> 06:59:37,440 not the limit of life this is what our 4704 06:59:41,750 --> 06:59:39,478 measurements can detect and if we found 4705 06:59:43,910 --> 06:59:41,760 an environment at 0.54 Water activity 4706 06:59:45,770 --> 06:59:43,920 with similar conditions to this 4707 06:59:48,110 --> 06:59:45,780 environment that we extrapolated it from 4708 06:59:49,968 --> 06:59:48,120 we would technically be able to detect 4709 06:59:51,708 --> 06:59:49,978 life in that environment 4710 06:59:53,448 --> 06:59:51,718 and this is also a really conservative 4711 06:59:56,090 --> 06:59:53,458 limit so 4712 06:59:58,310 --> 06:59:56,100 um we even upped the number of standard 4713 07:00:00,948 --> 06:59:58,320 deviations that we would normally do for 4714 07:00:02,868 --> 07:00:00,958 our like detection limit so if we were 4715 07:00:05,208 --> 07:00:02,878 to do like our data processing in the 4716 07:00:21,170 --> 07:00:05,218 normal way it might even be lower that 4717 07:00:27,410 --> 07:00:24,468 hey George eibel from Montana State I'm 4718 07:00:29,570 --> 07:00:27,420 just curious uh you're looking at the 4719 07:00:32,150 --> 07:00:29,580 Active cells were you did you look at 4720 07:00:36,830 --> 07:00:32,160 who they were at all whether that was by 4721 07:00:39,288 --> 07:00:36,840 fish or sequencing so in this study we 4722 07:00:42,548 --> 07:00:39,298 did not look at cell identity and we 4723 07:00:46,368 --> 07:00:42,558 focused on metabolism 4724 07:00:48,590 --> 07:00:46,378 in Western Australia I don't have plans 4725 07:00:50,990 --> 07:00:48,600 to look at the actual I don't know I 4726 07:00:52,610 --> 07:00:51,000 could look at the Active fraction of 4727 07:00:53,868 --> 07:00:52,620 cells from the bond cat analysis I 4728 07:00:55,548 --> 07:00:53,878 haven't decided if I want to go down 4729 07:00:58,430 --> 07:00:55,558 that road yet but in the next field site 4730 07:00:59,030 --> 07:00:58,440 we are planning on on doing that so 4731 07:01:02,510 --> 07:00:59,040 um 4732 07:01:04,070 --> 07:01:02,520 yeah not in this not in a city 4733 07:01:04,950 --> 07:01:04,080 all right thank you very much Emily yeah 4734 07:01:06,780 --> 07:01:04,960 thank you 4735 07:01:13,010 --> 07:01:06,790 [Music] 4736 07:01:17,690 --> 07:01:15,048 okay for our next speaker we have Zoe 4737 07:01:22,910 --> 07:01:17,700 havelena from the New Mexico Institute 4738 07:01:25,610 --> 07:01:24,708 that New Mexico Tech pretty short is 4739 07:01:28,010 --> 07:01:25,620 fine 4740 07:01:30,170 --> 07:01:28,020 um so hi I'm Zoe havlina I am a PhD 4741 07:01:31,610 --> 07:01:30,180 candidate from New Mexico Tech 4742 07:01:34,010 --> 07:01:31,620 um and I would like to just jump right 4743 07:01:34,868 --> 07:01:34,020 in and introduce my field site for this 4744 07:01:38,868 --> 07:01:34,878 project 4745 07:01:40,788 --> 07:01:38,878 which are two cave systems located in 4746 07:01:41,990 --> 07:01:40,798 central Italy so pictured here they're 4747 07:01:45,170 --> 07:01:42,000 very pretty 4748 07:01:46,730 --> 07:01:45,180 and what I can hopefully show you I'm 4749 07:01:49,368 --> 07:01:46,740 going to take us on a quick field trip 4750 07:01:52,548 --> 07:01:49,378 there is why these are potentially very 4751 07:01:55,490 --> 07:01:52,558 compelling sites for astrobiology or for 4752 07:01:59,208 --> 07:01:55,500 a Geo microbiologists such as myself 4753 07:02:01,430 --> 07:01:59,218 and so these caves form through a 4754 07:02:04,430 --> 07:02:01,440 somewhat rare mechanism which is known 4755 07:02:06,890 --> 07:02:04,440 as sulfuric acid speliogenesis so this 4756 07:02:10,430 --> 07:02:06,900 is a cave building process that's seen 4757 07:02:12,410 --> 07:02:10,440 only in a handful of caves worldwide and 4758 07:02:14,448 --> 07:02:12,420 only only a fraction of those can we 4759 07:02:17,390 --> 07:02:14,458 actually access those caves and see this 4760 07:02:19,190 --> 07:02:17,400 process actively happening today and so 4761 07:02:20,628 --> 07:02:19,200 that's what I'm showing you here so 4762 07:02:22,610 --> 07:02:20,638 these are all images from one of my 4763 07:02:23,510 --> 07:02:22,620 field sites which is a fresasi Cave 4764 07:02:25,730 --> 07:02:23,520 System 4765 07:02:28,070 --> 07:02:25,740 and what you're looking at in this image 4766 07:02:30,890 --> 07:02:28,080 here on the left this is a stream this 4767 07:02:32,810 --> 07:02:30,900 is the groundwater level of the cave and 4768 07:02:35,030 --> 07:02:32,820 it's enriched in hydrogen sulfide and 4769 07:02:36,830 --> 07:02:35,040 this hydrogen sulfide degases where 4770 07:02:40,128 --> 07:02:36,840 there's voids in the host Rock of the 4771 07:02:42,948 --> 07:02:40,138 cave and this hydrogen sulfide fuels 4772 07:02:44,930 --> 07:02:42,958 very a robust microbial communities that 4773 07:02:46,910 --> 07:02:44,940 are thriving off of the energy in this 4774 07:02:49,670 --> 07:02:46,920 otherwise very leukotrophic environment 4775 07:02:52,368 --> 07:02:49,680 and this is seen kind of conspicuously 4776 07:02:56,150 --> 07:02:52,378 in the forms of these charismatically 4777 07:02:58,548 --> 07:02:56,160 named snodite biofilms which proliferate 4778 07:02:59,930 --> 07:02:58,558 in these areas of the cave here's 4779 07:03:01,910 --> 07:02:59,940 another picture of what they look like 4780 07:03:04,968 --> 07:03:01,920 and we also sometimes see if you can see 4781 07:03:07,190 --> 07:03:04,978 the yellow dots native sulfur that can 4782 07:03:09,850 --> 07:03:07,200 precipitate in these areas as well 4783 07:03:12,230 --> 07:03:09,860 and these are primarily composed of 4784 07:03:13,968 --> 07:03:12,240 citythial bacillus which is a sulfur 4785 07:03:16,010 --> 07:03:13,978 oxidizing bacteria 4786 07:03:18,350 --> 07:03:16,020 but what I'm interested in for the 4787 07:03:20,690 --> 07:03:18,360 context of my project are all of these 4788 07:03:23,690 --> 07:03:20,700 white I don't know if you can see my 4789 07:03:24,968 --> 07:03:23,700 pointer here these white clumpy minerals 4790 07:03:27,230 --> 07:03:24,978 here and this is actually 4791 07:03:29,330 --> 07:03:27,240 microcrystalline gypsum this 4792 07:03:31,190 --> 07:03:29,340 precipitates in part kind of as a 4793 07:03:33,590 --> 07:03:31,200 consequence of this microbial activity 4794 07:03:35,510 --> 07:03:33,600 because these sulfur oxidizers are 4795 07:03:38,448 --> 07:03:35,520 producing sulfuric acid which is 4796 07:03:41,150 --> 07:03:38,458 obviously highly corrosive when you have 4797 07:03:43,430 --> 07:03:41,160 a carbonate host Rock and so this gypsum 4798 07:03:46,788 --> 07:03:43,440 is precipitating as a replacement as 4799 07:03:50,510 --> 07:03:46,798 this host Rockets corroded 4800 07:03:53,750 --> 07:03:50,520 and it's highly acidic so pH is usually 4801 07:03:55,788 --> 07:03:53,760 zero to one and what happens is that 4802 07:03:58,548 --> 07:03:55,798 this gypsum can build up in these cave 4803 07:04:00,288 --> 07:03:58,558 systems and remain there essentially as 4804 07:04:01,968 --> 07:04:00,298 long as you don't have any Waters that 4805 07:04:04,010 --> 07:04:01,978 come in and wash it away and so that's 4806 07:04:05,810 --> 07:04:04,020 what I'm showing on this image on the 4807 07:04:08,810 --> 07:04:05,820 far right here this is one of these like 4808 07:04:11,390 --> 07:04:08,820 massive gypsum deposits that exists in a 4809 07:04:13,310 --> 07:04:11,400 part of the Versace cave that hasn't 4810 07:04:15,890 --> 07:04:13,320 been exposed to this active sulfide 4811 07:04:17,690 --> 07:04:15,900 degassing for maybe a hundred to two 4812 07:04:21,530 --> 07:04:17,700 hundred thousand years 4813 07:04:24,048 --> 07:04:21,540 and so we see sulfates and gypsum on 4814 07:04:26,510 --> 07:04:24,058 other locations notably the surface of 4815 07:04:28,628 --> 07:04:26,520 Mars so I'm showing you data here as it 4816 07:04:31,190 --> 07:04:28,638 relates to the Gale crater 4817 07:04:34,128 --> 07:04:31,200 and there's some evidence or some 4818 07:04:36,110 --> 07:04:34,138 thinking that this sulfates could have 4819 07:04:38,990 --> 07:04:36,120 also precipitated under acidic 4820 07:04:40,548 --> 07:04:39,000 conditions so potentially these are 4821 07:04:42,708 --> 07:04:40,558 thought of as 4822 07:04:45,650 --> 07:04:42,718 places where we might look for for 4823 07:04:48,048 --> 07:04:45,660 evidence of life and on the Earth's 4824 07:04:49,490 --> 07:04:48,058 surface the analogs that we have there 4825 07:04:50,948 --> 07:04:49,500 are several and these have been well 4826 07:04:54,530 --> 07:04:50,958 studied by other teams of 4827 07:04:56,330 --> 07:04:54,540 astrobiologists but what is novel um or 4828 07:05:00,110 --> 07:04:56,340 the argument I'm making for these caves 4829 07:05:02,150 --> 07:05:00,120 is that this is an ecosystem that as I 4830 07:05:04,788 --> 07:05:02,160 just showed you is fueled by chemo litho 4831 07:05:07,010 --> 07:05:04,798 autotrophy so these kind of alternative 4832 07:05:09,890 --> 07:05:07,020 Lifestyles and so potentially studying 4833 07:05:11,590 --> 07:05:09,900 the gypsum and its ability to preserve 4834 07:05:14,690 --> 07:05:11,600 or not preserve 4835 07:05:17,510 --> 07:05:14,700 biosignatures is is kind of a novel 4836 07:05:19,368 --> 07:05:17,520 aspect and gets away from surface world 4837 07:05:21,230 --> 07:05:19,378 where we sometimes see the signatures 4838 07:05:24,048 --> 07:05:21,240 mostly of things that are photosynthetic 4839 07:05:25,910 --> 07:05:24,058 and so in the context of this talk when 4840 07:05:27,770 --> 07:05:25,920 I'm talking about life detection or I'm 4841 07:05:30,590 --> 07:05:27,780 talking about signatures I'm talking 4842 07:05:32,628 --> 07:05:30,600 about lipid biomarkers specifically and 4843 07:05:33,890 --> 07:05:32,638 so what I'm showing you here are some 4844 07:05:36,170 --> 07:05:33,900 types of these they were kind of 4845 07:05:38,270 --> 07:05:36,180 explained earlier these ones on the left 4846 07:05:40,788 --> 07:05:38,280 which are those hopenoids so these are 4847 07:05:43,490 --> 07:05:40,798 produced by bacteria and these can be 4848 07:05:45,490 --> 07:05:43,500 functionalized and then they have this 4849 07:05:48,890 --> 07:05:45,500 very recalcitrant 4850 07:05:51,110 --> 07:05:48,900 backbone structure this hoping that is 4851 07:05:53,208 --> 07:05:51,120 this diagenetic structure that can 4852 07:05:55,610 --> 07:05:53,218 persist in some terrestrial environments 4853 07:05:58,150 --> 07:05:55,620 for potentially millions of years and 4854 07:06:00,650 --> 07:05:58,160 then on the right these are 4855 07:06:04,010 --> 07:06:00,660 gdgts from archaea so kind of a similar 4856 07:06:05,990 --> 07:06:04,020 lipid biomarker and the these specific 4857 07:06:08,330 --> 07:06:06,000 structures that I'm showing you are ones 4858 07:06:11,270 --> 07:06:08,340 that have been classified from those 4859 07:06:12,830 --> 07:06:11,280 snodite biofilms that I showed you in 4860 07:06:14,990 --> 07:06:12,840 their earlier image 4861 07:06:17,448 --> 07:06:15,000 and so knowing what we already know 4862 07:06:19,968 --> 07:06:17,458 about these cave systems which is that 4863 07:06:22,548 --> 07:06:19,978 we have gypsum that is precipitating in 4864 07:06:25,670 --> 07:06:22,558 in very close association with microbial 4865 07:06:28,368 --> 07:06:25,680 activity that's kind of these microbes 4866 07:06:31,010 --> 07:06:28,378 that are using an alternative lifestyle 4867 07:06:33,230 --> 07:06:31,020 and we know that some of these organisms 4868 07:06:34,910 --> 07:06:33,240 like that aciditythylbacillus are 4869 07:06:38,330 --> 07:06:34,920 capable of producing these lipid 4870 07:06:41,510 --> 07:06:38,340 biomarkers and this gypsum is kicking 4871 07:06:44,208 --> 07:06:41,520 around in this cave for a little bit of 4872 07:06:46,310 --> 07:06:44,218 time we sort of used what we know to 4873 07:06:47,628 --> 07:06:46,320 form these questions about things that 4874 07:06:49,610 --> 07:06:47,638 we don't know 4875 07:06:51,770 --> 07:06:49,620 um we don't actually know or going into 4876 07:06:54,170 --> 07:06:51,780 the study no one had ever looked at what 4877 07:06:55,670 --> 07:06:54,180 microbes are colonizing the surface of 4878 07:06:57,830 --> 07:06:55,680 the gypsum itself 4879 07:07:01,368 --> 07:06:57,840 and we don't know if those organisms 4880 07:07:03,708 --> 07:07:01,378 produce their own lipid biomarker Suite 4881 07:07:05,990 --> 07:07:03,718 if we'll be able to characterize that or 4882 07:07:08,750 --> 07:07:06,000 detect it in the gypsum at all and then 4883 07:07:11,150 --> 07:07:08,760 if we do does that persist in this 4884 07:07:14,270 --> 07:07:11,160 gypsum that has been existing in this 4885 07:07:17,030 --> 07:07:14,280 cave for a longer period of time 4886 07:07:18,830 --> 07:07:17,040 and so I won't go into the Weeds on 4887 07:07:20,868 --> 07:07:18,840 these methods here but I just want to 4888 07:07:22,788 --> 07:07:20,878 highlight that we're using kind of a few 4889 07:07:25,190 --> 07:07:22,798 different approaches to answer some of 4890 07:07:27,350 --> 07:07:25,200 these questions so using some sort of 4891 07:07:30,110 --> 07:07:27,360 classic molecular biology techniques 4892 07:07:31,788 --> 07:07:30,120 amplicon sequencing and metagenomics to 4893 07:07:34,548 --> 07:07:31,798 characterize those microbial communities 4894 07:07:37,070 --> 07:07:34,558 and then using some organic geochemical 4895 07:07:39,288 --> 07:07:37,080 techniques to try to characterize those 4896 07:07:42,288 --> 07:07:39,298 lipid biomarkers 4897 07:07:45,048 --> 07:07:42,298 and so some of the data that I've had 4898 07:07:47,690 --> 07:07:45,058 um is that these gypsum surfaces are in 4899 07:07:49,548 --> 07:07:47,700 fact colonized by microbes and so what 4900 07:07:52,070 --> 07:07:49,558 I'm showing you here is amplicon 4901 07:07:54,948 --> 07:07:52,080 sequencing data so that's 16sr in our 4902 07:07:57,468 --> 07:07:54,958 sequencing that tells us who's there 4903 07:07:59,150 --> 07:07:57,478 and what I want you to take away from 4904 07:08:01,730 --> 07:07:59,160 this graph is that I'm plotting two 4905 07:08:04,010 --> 07:08:01,740 things here on the left to this access 4906 07:08:06,468 --> 07:08:04,020 and the blue dots is showing the percent 4907 07:08:09,590 --> 07:08:06,478 of that acid bacillus so that's that 4908 07:08:12,350 --> 07:08:09,600 main sulfate oxidizing bacteria that we 4909 07:08:14,270 --> 07:08:12,360 see in those snodite biofilms and then 4910 07:08:17,330 --> 07:08:14,280 on the right I'm showing in this orange 4911 07:08:19,968 --> 07:08:17,340 I'm showing you the overall diversity of 4912 07:08:22,430 --> 07:08:19,978 these samples and so all these dots are 4913 07:08:24,770 --> 07:08:22,440 gypsum samples that we're taking at kind 4914 07:08:27,948 --> 07:08:24,780 of varying distances from that active 4915 07:08:30,830 --> 07:08:27,958 lead degassing sulfate extreme 4916 07:08:32,448 --> 07:08:30,840 and just a reminder so these statite 4917 07:08:35,270 --> 07:08:32,458 biofilms that have been previously 4918 07:08:37,010 --> 07:08:35,280 characterized are around 70 percent of 4919 07:08:40,070 --> 07:08:37,020 citythal bacillus and so the main 4920 07:08:42,350 --> 07:08:40,080 takeaway is that are samples of gypsum 4921 07:08:43,910 --> 07:08:42,360 are far more diverse than that you know 4922 07:08:45,948 --> 07:08:43,920 even at this kind of like best case 4923 07:08:48,350 --> 07:08:45,958 scenario where we're the closest to the 4924 07:08:50,390 --> 07:08:48,360 sulfate extreme we're really not seeing 4925 07:08:51,468 --> 07:08:50,400 anywhere near 70 percent of city-thal 4926 07:08:54,350 --> 07:08:51,478 bacillus 4927 07:08:56,448 --> 07:08:54,360 and so this is data from that other cave 4928 07:08:58,368 --> 07:08:56,458 that I've studied and I don't have that 4929 07:08:59,990 --> 07:08:58,378 nice distance gradient but again it's 4930 07:09:01,670 --> 07:09:00,000 plotting the same things and I've just 4931 07:09:03,770 --> 07:09:01,680 kind of broadly lumped these samples 4932 07:09:06,770 --> 07:09:03,780 together in terms of like high level of 4933 07:09:09,350 --> 07:09:06,780 sulfide medium level lower levels and 4934 07:09:12,110 --> 07:09:09,360 again we see a similar Trend we also see 4935 07:09:14,208 --> 07:09:12,120 low levels of acetyl bacillus and in 4936 07:09:16,910 --> 07:09:14,218 fact we see a heck of a lot of archaea 4937 07:09:19,850 --> 07:09:16,920 too so some of these samples were almost 4938 07:09:21,890 --> 07:09:19,860 entirely archaea and why I talk about 4939 07:09:24,350 --> 07:09:21,900 acetyl bacillus and I talk about the 4940 07:09:26,330 --> 07:09:24,360 diversity of these samples is that you 4941 07:09:29,330 --> 07:09:26,340 know we know acetyl bacillus is capable 4942 07:09:31,670 --> 07:09:29,340 of producing lipid biomarkers but it's 4943 07:09:33,530 --> 07:09:31,680 one of the bacteria that can and in fact 4944 07:09:35,750 --> 07:09:33,540 a lot of them can't and so this 4945 07:09:38,270 --> 07:09:35,760 potentially has implications when we 4946 07:09:40,310 --> 07:09:38,280 think about you know are there things 4947 07:09:43,010 --> 07:09:40,320 that is in this gypsum that is producing 4948 07:09:45,968 --> 07:09:43,020 lipid biomarkers or aren't there 4949 07:09:48,948 --> 07:09:45,978 and we can kind of get at this um 4950 07:09:50,930 --> 07:09:48,958 indirectly through metagenomics and so 4951 07:09:52,490 --> 07:09:50,940 again metagenomics is looking at all of 4952 07:09:55,128 --> 07:09:52,500 the genes that are present in a 4953 07:09:57,350 --> 07:09:55,138 particular environmental sample and so 4954 07:09:59,030 --> 07:09:57,360 far I have only reconstructed a single 4955 07:10:02,150 --> 07:09:59,040 metagenome and this is from a native 4956 07:10:03,530 --> 07:10:02,160 sulfur deposit but I did do some Gene 4957 07:10:05,990 --> 07:10:03,540 searching and I was looking for this 4958 07:10:08,090 --> 07:10:06,000 squaly and hoping cyclase Gene which 4959 07:10:10,730 --> 07:10:08,100 forms a critical precursor to making 4960 07:10:13,310 --> 07:10:10,740 those hopenoid lipid biomarkers and I 4961 07:10:15,530 --> 07:10:13,320 did find some copies of that but again I 4962 07:10:17,930 --> 07:10:15,540 also found a ton of archaea and two of 4963 07:10:20,990 --> 07:10:17,940 the high quality bins that I was able to 4964 07:10:22,670 --> 07:10:21,000 assemble were these two kind of Novel 4965 07:10:25,250 --> 07:10:22,680 archaea that have potentially an 4966 07:10:26,868 --> 07:10:25,260 interesting symbiotic relationship and I 4967 07:10:29,090 --> 07:10:26,878 would love to talk about that more but 4968 07:10:30,530 --> 07:10:29,100 that's kind of a whole other talk so I'm 4969 07:10:33,288 --> 07:10:30,540 just going to leave it at that with this 4970 07:10:34,250 --> 07:10:33,298 complicated figure here on the right 4971 07:10:37,430 --> 07:10:34,260 um 4972 07:10:39,410 --> 07:10:37,440 so it you might be guessing or kind of 4973 07:10:42,230 --> 07:10:39,420 wondering why I've only gotten one 4974 07:10:44,270 --> 07:10:42,240 metagenome so far and really it's 4975 07:10:47,330 --> 07:10:44,280 because the overall biomass in these 4976 07:10:49,850 --> 07:10:47,340 gypsum samples is very low and so what 4977 07:10:52,070 --> 07:10:49,860 I'm showing you in this picture here so 4978 07:10:54,948 --> 07:10:52,080 this is microscopy this is dappy 4979 07:10:57,590 --> 07:10:54,958 staining so looking at cells and so you 4980 07:11:01,010 --> 07:10:57,600 see hopefully you can see just a few 4981 07:11:03,590 --> 07:11:01,020 blue dots those are cells and on the 4982 07:11:07,010 --> 07:11:03,600 right this is showing them sitting in a 4983 07:11:08,570 --> 07:11:07,020 bathtub full of gypsum micro crystals 4984 07:11:11,270 --> 07:11:08,580 and so when you just kind of 4985 07:11:13,968 --> 07:11:11,280 contextualize this low number of cells 4986 07:11:15,770 --> 07:11:13,978 in in the vast array of all of these 4987 07:11:17,810 --> 07:11:15,780 minerals 4988 07:11:19,490 --> 07:11:17,820 there's not a whole lot going on and in 4989 07:11:21,948 --> 07:11:19,500 fact some of our preliminary total 4990 07:11:24,650 --> 07:11:21,958 organic carbon measurements are less 4991 07:11:27,410 --> 07:11:24,660 than one percent or even a fraction of a 4992 07:11:29,690 --> 07:11:27,420 percent and so 4993 07:11:31,250 --> 07:11:29,700 that all leads to kind of some 4994 07:11:33,350 --> 07:11:31,260 complications with trying to actually 4995 07:11:35,628 --> 07:11:33,360 extract some of these lipid biomarkers 4996 07:11:38,150 --> 07:11:35,638 and so this side of the project is still 4997 07:11:40,310 --> 07:11:38,160 an active protocol development we 4998 07:11:41,990 --> 07:11:40,320 haven't seen anything yet 4999 07:11:44,628 --> 07:11:42,000 um and so we've had to kind of scale up 5000 07:11:47,448 --> 07:11:44,638 our extraction we're hoping to extract a 5001 07:11:48,830 --> 07:11:47,458 lot more gypsum and and I'm hoping that 5002 07:11:51,110 --> 07:11:48,840 that's something I'll be able to talk 5003 07:11:53,090 --> 07:11:51,120 about more in the future but I just want 5004 07:11:56,448 --> 07:11:53,100 to return to sort of The Guiding 5005 07:11:59,030 --> 07:11:56,458 question of this of this study which is 5006 07:12:00,530 --> 07:11:59,040 you know looking at these 5007 07:12:03,530 --> 07:12:00,540 very 5008 07:12:06,170 --> 07:12:03,540 um interesting microbial Dynamics the 5009 07:12:09,110 --> 07:12:06,180 way that the stripsum is formed we see a 5010 07:12:11,208 --> 07:12:09,120 lot of we see biofilms existing where 5011 07:12:12,350 --> 07:12:11,218 where the zone is forming but we 5012 07:12:14,930 --> 07:12:12,360 don't know 5013 07:12:17,390 --> 07:12:14,940 if there's biomarkers that are preserved 5014 07:12:19,730 --> 07:12:17,400 or not and I have to leave that question 5015 07:12:21,708 --> 07:12:19,740 open at this time 5016 07:12:22,548 --> 07:12:21,718 um but hopefully I can answer it in the 5017 07:12:25,090 --> 07:12:22,558 future 5018 07:12:28,670 --> 07:12:25,100 so I think I will just leave off there 5019 07:12:31,250 --> 07:12:28,680 and I wouldn't be able to do this work 5020 07:12:33,948 --> 07:12:31,260 without I have a lot of very fantastic 5021 07:12:35,510 --> 07:12:33,958 collaborators and funding sources and I 5022 07:12:37,788 --> 07:12:35,520 would especially like to thank all the 5023 07:12:41,570 --> 07:12:37,798 folks at the astrobiology analytical 5024 07:12:43,250 --> 07:12:41,580 laboratory at Goddard and I think that I 5025 07:12:43,960 --> 07:12:43,260 have some time for questions so thank 5026 07:12:50,810 --> 07:12:43,970 you 5027 07:13:03,830 --> 07:12:50,820 [Applause] 5028 07:13:09,468 --> 07:13:06,770 hey um I'm bunny Chase I'm from the jet 5029 07:13:11,270 --> 07:13:09,478 propulsion laboratory I really love this 5030 07:13:12,890 --> 07:13:11,280 question you're asking and like the way 5031 07:13:14,208 --> 07:13:12,900 that you're trying to attack it and I 5032 07:13:17,390 --> 07:13:14,218 was wondering 5033 07:13:20,448 --> 07:13:17,400 a lot of the lipid biomarkers that you 5034 07:13:22,310 --> 07:13:20,458 talked about looking for they as you 5035 07:13:24,530 --> 07:13:22,320 said can be preserved for a few millions 5036 07:13:26,510 --> 07:13:24,540 of years but what about the more stable 5037 07:13:28,548 --> 07:13:26,520 versions like looking for her pains 5038 07:13:31,250 --> 07:13:28,558 rather than hope Knowles are you also 5039 07:13:33,410 --> 07:13:31,260 looking for those yeah yeah we are I 5040 07:13:35,330 --> 07:13:33,420 didn't really explain that super well 5041 07:13:37,490 --> 07:13:35,340 but we are hoping to look for helping 5042 07:13:39,410 --> 07:13:37,500 hoping to look for Hope pains as well 5043 07:13:42,468 --> 07:13:39,420 yeah 5044 07:13:43,910 --> 07:13:42,478 and um what do you think like the 5045 07:13:46,070 --> 07:13:43,920 preservation 5046 07:13:48,350 --> 07:13:46,080 is in this cave would be for the 5047 07:13:51,708 --> 07:13:48,360 molecules and how similar is that to 5048 07:13:54,410 --> 07:13:51,718 Mars yeah I think that that is kind of 5049 07:13:57,350 --> 07:13:54,420 the key question for sure 5050 07:14:02,270 --> 07:13:59,288 I don't know if that's something that I 5051 07:14:03,650 --> 07:14:02,280 want to dive into right now but I think 5052 07:14:05,390 --> 07:14:03,660 we should talk about it later for sure 5053 07:14:06,530 --> 07:14:05,400 I'm curious to hear your thoughts on it 5054 07:14:08,628 --> 07:14:06,540 as well 5055 07:14:12,770 --> 07:14:08,638 um obviously this is a oxidizing 5056 07:14:15,770 --> 07:14:12,780 environment it's it's acidic it's wet so 5057 07:14:17,810 --> 07:14:15,780 it has a lot that could maybe not be 5058 07:14:19,190 --> 07:14:17,820 preserving things but 5059 07:14:21,610 --> 07:14:19,200 um you know certainly folks have done 5060 07:14:24,830 --> 07:14:21,620 similar research and and have found 5061 07:14:26,990 --> 07:14:24,840 biomarkers in in Gypsum and other 5062 07:14:33,530 --> 07:14:27,000 environments on Earth so 5063 07:14:38,810 --> 07:14:36,948 any last questions for Zoe 5064 07:14:44,330 --> 07:14:38,820 okay thank you so much oh wait there's 5065 07:14:47,930 --> 07:14:46,010 hey so I have a question about the 5066 07:14:50,510 --> 07:14:47,940 microcrystalline nature of that gypsum 5067 07:14:52,730 --> 07:14:50,520 so what do you think that might what's 5068 07:14:54,830 --> 07:14:52,740 your hypothesis for structurally how 5069 07:14:56,330 --> 07:14:54,840 that might affect preservation of Bio 5070 07:14:57,708 --> 07:14:56,340 signatures as opposed to other kinds of 5071 07:14:59,930 --> 07:14:57,718 gypsum that might happen on the surface 5072 07:15:01,310 --> 07:14:59,940 yeah I think that that's a really good 5073 07:15:03,110 --> 07:15:01,320 question 5074 07:15:05,570 --> 07:15:03,120 um 5075 07:15:07,010 --> 07:15:05,580 I guess you know off the top of my head 5076 07:15:08,750 --> 07:15:07,020 I would say that 5077 07:15:11,030 --> 07:15:08,760 I don't know if we're gonna get it like 5078 07:15:12,530 --> 07:15:11,040 doesn't really layer I think necessarily 5079 07:15:14,628 --> 07:15:12,540 in the way that we see in like 5080 07:15:16,730 --> 07:15:14,638 evaporative gypsum 5081 07:15:19,128 --> 07:15:16,740 um how that may or may not you know 5082 07:15:20,810 --> 07:15:19,138 factor into biosignature preservation I 5083 07:15:22,070 --> 07:15:20,820 don't I can't really speak to that but 5084 07:15:24,468 --> 07:15:22,080 it is I think it's definitely a really 5085 07:15:26,150 --> 07:15:24,478 interesting difference 5086 07:15:27,288 --> 07:15:26,160 um that we see in this gypsum for sure 5087 07:15:30,170 --> 07:15:27,298 and it's like 5088 07:15:31,670 --> 07:15:30,180 it's I didn't really show any of the 5089 07:15:33,708 --> 07:15:31,680 like there's that one picture that I 5090 07:15:36,170 --> 07:15:33,718 showed of the gypsum but it's it's crazy 5091 07:15:37,490 --> 07:15:36,180 it's like you know we call it Rock in 5092 07:15:39,770 --> 07:15:37,500 name only 5093 07:15:41,510 --> 07:15:39,780 um it's it's like goo 5094 07:15:43,310 --> 07:15:41,520 um you go to sample it and it's almost 5095 07:15:46,128 --> 07:15:43,320 like a non-Newtonian fluid it like just 5096 07:15:49,128 --> 07:15:46,138 kind of like oozes um which is super 5097 07:15:53,628 --> 07:15:49,138 wild and and it's kind of difficult to 5098 07:16:02,810 --> 07:15:55,710 all right thank you so much Zoe 5099 07:16:02,810 --> 07:16:02,820 [Applause] 5100 07:16:06,650 --> 07:16:04,250 okay 5101 07:16:18,948 --> 07:16:06,660 so our next speaker is Kimberly Sinclair 5102 07:16:23,510 --> 07:16:22,368 hi I'm Kimberly Sinclair I'm from the 5103 07:16:25,070 --> 07:16:23,520 University of Washington department of 5104 07:16:28,368 --> 07:16:25,080 Earth and space Sciences I'm working 5105 07:16:29,810 --> 07:16:28,378 with David catling and Tim Elam I'm 5106 07:16:31,610 --> 07:16:29,820 going to talk to you guys about this 5107 07:16:33,230 --> 07:16:31,620 project the mineralogy of evaporites and 5108 07:16:34,968 --> 07:16:33,240 sediments in the alkaline phosphate Rich 5109 07:16:36,530 --> 07:16:34,978 Lakes so the Caribou Plateau which is 5110 07:16:40,250 --> 07:16:36,540 work I've been doing with Sebastian Haas 5111 07:16:41,510 --> 07:16:40,260 and is funded by the Simons Foundation 5112 07:16:42,948 --> 07:16:41,520 okay so I want to give you a bit of 5113 07:16:44,690 --> 07:16:42,958 background about the phosphorus problem 5114 07:16:46,850 --> 07:16:44,700 in astrobiology because I know we're all 5115 07:16:48,830 --> 07:16:46,860 coming from very different backgrounds 5116 07:16:50,030 --> 07:16:48,840 uh there's a lot of biology talks this 5117 07:16:52,250 --> 07:16:50,040 morning though so I'm sure a lot of you 5118 07:16:54,548 --> 07:16:52,260 guys are caught up on this but uh so we 5119 07:16:57,770 --> 07:16:54,558 all know DNA on the right hand side here 5120 07:16:59,930 --> 07:16:57,780 has this sugar phosphate backbone and 5121 07:17:01,610 --> 07:16:59,940 then you have your base pairs or if you 5122 07:17:03,350 --> 07:17:01,620 zoom in closer you're seeing your 5123 07:17:06,650 --> 07:17:03,360 phosphate group your sugar and your 5124 07:17:08,690 --> 07:17:06,660 nuclear base here and in order to get 5125 07:17:11,150 --> 07:17:08,700 this phosphate to incorporate into the 5126 07:17:13,670 --> 07:17:11,160 nucleotide you need very high levels of 5127 07:17:15,770 --> 07:17:13,680 phosphate and this has been shown by 5128 07:17:18,110 --> 07:17:15,780 research done by powder at all in 2009 5129 07:17:19,430 --> 07:17:18,120 so this question we want to ask is how 5130 07:17:21,770 --> 07:17:19,440 much phosphorus is actually available 5131 07:17:22,670 --> 07:17:21,780 for Prebiotic phosphorylation on early 5132 07:17:24,770 --> 07:17:22,680 Earth 5133 07:17:26,628 --> 07:17:24,780 and even though we need these very high 5134 07:17:28,250 --> 07:17:26,638 concentrations of phosphate up to one 5135 07:17:30,830 --> 07:17:28,260 molar in Prebiotic phosphorylation 5136 07:17:32,750 --> 07:17:30,840 experiments we only see very low 5137 07:17:34,788 --> 07:17:32,760 concentrations of phosphate in the 5138 07:17:36,890 --> 07:17:34,798 environment close to the micromolar 5139 07:17:38,570 --> 07:17:36,900 level and that's because in natural 5140 07:17:40,490 --> 07:17:38,580 Waters phosphate will combine with 5141 07:17:43,128 --> 07:17:40,500 calcium and Fallout of solution as an 5142 07:17:45,830 --> 07:17:43,138 insoluble mineral known as appetite or 5143 07:17:48,048 --> 07:17:45,840 calcium phosphate before reaching very 5144 07:17:49,368 --> 07:17:48,058 high concentrations so there's a bit of 5145 07:17:51,530 --> 07:17:49,378 a problem here and that's what we call 5146 07:17:53,330 --> 07:17:51,540 the phosphorus problem 5147 07:17:56,330 --> 07:17:53,340 uh We've proposed a solution to the 5148 07:17:58,310 --> 07:17:56,340 phosphorus problem uh in a paper by 5149 07:18:00,770 --> 07:17:58,320 toner and catling in 2020 the hypothesis 5150 07:18:02,570 --> 07:18:00,780 was stated that abundant carbonate leads 5151 07:18:05,090 --> 07:18:02,580 to calcite formation calcite being 5152 07:18:07,910 --> 07:18:05,100 calcium carbonate thus suppressing the 5153 07:18:09,350 --> 07:18:07,920 calcium phosphate mineral formation and 5154 07:18:11,270 --> 07:18:09,360 leaving phosphorus in solution to 5155 07:18:13,010 --> 07:18:11,280 concentrate to higher levels 5156 07:18:14,930 --> 07:18:13,020 so in order to test this Theory we 5157 07:18:17,448 --> 07:18:14,940 visited the most phosphorus Rich lake in 5158 07:18:19,730 --> 07:18:17,458 the world uh this plot on the right hand 5159 07:18:21,410 --> 07:18:19,740 side is from toner and catling 2020 you 5160 07:18:23,150 --> 07:18:21,420 see a very high phosphorus 5161 07:18:25,610 --> 07:18:23,160 concentrations in these lakes on the top 5162 07:18:27,110 --> 07:18:25,620 right side which are good enough in last 5163 07:18:29,208 --> 07:18:27,120 chance Lake and so that's where we 5164 07:18:30,530 --> 07:18:29,218 wanted to visit to understand why you're 5165 07:18:32,750 --> 07:18:30,540 getting these very high concentrations 5166 07:18:34,670 --> 07:18:32,760 of phosphorus we can then apply our 5167 07:18:36,530 --> 07:18:34,680 understanding of these Lakes to possible 5168 07:18:39,590 --> 07:18:36,540 analog Lakes on Prebiotic Earth where 5169 07:18:41,208 --> 07:18:39,600 origin of life could have happened 5170 07:18:42,770 --> 07:18:41,218 so a little bit about these Lakes Last 5171 07:18:45,048 --> 07:18:42,780 Chance in good enough Lakes are 5172 07:18:46,368 --> 07:18:45,058 carbonate Rich alkaline soda lakes on 5173 07:18:49,070 --> 07:18:46,378 the Caribou plateau in British Columbia 5174 07:18:50,810 --> 07:18:49,080 Canada left hand side you see the map of 5175 07:18:53,090 --> 07:18:50,820 British Columbia here in this green 5176 07:18:55,070 --> 07:18:53,100 swath is the Caribou Plateau it's right 5177 07:18:56,868 --> 07:18:55,080 East of those coastal mountains not too 5178 07:18:58,310 --> 07:18:56,878 far north of Vancouver 5179 07:19:00,048 --> 07:18:58,320 if you were to zoom in on Google Maps 5180 07:19:03,948 --> 07:19:00,058 you would see the lakes here good enough 5181 07:19:05,810 --> 07:19:03,958 Lake here and last chance Lake here 5182 07:19:07,788 --> 07:19:05,820 um they both have very high phosphate 5183 07:19:10,368 --> 07:19:07,798 concentrations but particularly Last 5184 07:19:12,048 --> 07:19:10,378 Chance Lake gets up to 37 millimolar of 5185 07:19:14,448 --> 07:19:12,058 phosphorus which is very high in 5186 07:19:16,610 --> 07:19:14,458 comparison to that micromolar level that 5187 07:19:18,590 --> 07:19:16,620 we're usually seeing in natural Waters 5188 07:19:21,048 --> 07:19:18,600 and this is an image of Last Chance Lake 5189 07:19:22,250 --> 07:19:21,058 taken in November 2021 which is what it 5190 07:19:23,868 --> 07:19:22,260 looks like from the ground level so 5191 07:19:26,510 --> 07:19:23,878 you're seeing it form into these sort of 5192 07:19:28,190 --> 07:19:26,520 brine pools 5193 07:19:30,048 --> 07:19:28,200 so a little bit of context from these 5194 07:19:32,208 --> 07:19:30,058 Lakes they're too small less than 5195 07:19:34,610 --> 07:19:32,218 kilometer squared shallow closed Basin 5196 07:19:37,250 --> 07:19:34,620 lakes with sodium carbonate sulfate 5197 07:19:39,350 --> 07:19:37,260 chlorine brines these are typical major 5198 07:19:40,430 --> 07:19:39,360 ions of soda Lakes developed on basaltic 5199 07:19:43,070 --> 07:19:40,440 Rock 5200 07:19:45,230 --> 07:19:43,080 their sulfate potassium phosphate and 5201 07:19:47,208 --> 07:19:45,240 magnesium are abundant whereas calcium 5202 07:19:48,948 --> 07:19:47,218 iron silicon and dissolved inorganic 5203 07:19:50,270 --> 07:19:48,958 nitrogen are present at very low 5204 07:19:53,510 --> 07:19:50,280 concentrations 5205 07:19:56,330 --> 07:19:53,520 the salinity reaches up to 462 grams per 5206 07:19:58,548 --> 07:19:56,340 liter which is about 13 times seawater 5207 07:20:02,030 --> 07:19:58,558 salinity so they're very salty 5208 07:20:03,468 --> 07:20:02,040 and the pH ranges from 9.7 to 10.7 in 5209 07:20:05,208 --> 07:20:03,478 both of these Lakes depending on the 5210 07:20:07,670 --> 07:20:05,218 time of year and the location in The 5211 07:20:10,368 --> 07:20:07,680 Lakes because they do get spring in fed 5212 07:20:14,150 --> 07:20:10,378 from surrounding rivers and such 5213 07:20:15,830 --> 07:20:14,160 or sorry from groundwater not reverse 5214 07:20:18,048 --> 07:20:15,840 so we wanted to go and visit these Lakes 5215 07:20:19,910 --> 07:20:18,058 over different seasons in order to 5216 07:20:21,830 --> 07:20:19,920 understand how the mineralogy of 5217 07:20:23,930 --> 07:20:21,840 different precipitates and evaporites as 5218 07:20:25,670 --> 07:20:23,940 well as precipitates in the sediments 5219 07:20:27,530 --> 07:20:25,680 change 5220 07:20:29,090 --> 07:20:27,540 um so we went in winter summer and fall 5221 07:20:32,150 --> 07:20:29,100 and you can see the corresponding 5222 07:20:33,890 --> 07:20:32,160 pictures here in Winter 2021 you see 5223 07:20:35,390 --> 07:20:33,900 these brine pools starting to freeze 5224 07:20:38,270 --> 07:20:35,400 over 5225 07:20:40,010 --> 07:20:38,280 um and summer 22 to 2022 it enters this 5226 07:20:41,930 --> 07:20:40,020 ephemeral Lake stage where it has enough 5227 07:20:43,010 --> 07:20:41,940 water that it actually covers the entire 5228 07:20:45,770 --> 07:20:43,020 surface 5229 07:20:47,810 --> 07:20:45,780 and then in Autumn 2022 these brine 5230 07:20:49,610 --> 07:20:47,820 pools are drying out into Salt Flats and 5231 07:20:52,850 --> 07:20:49,620 so there's basically no water left in 5232 07:20:54,288 --> 07:20:52,860 this system at all it's just salt 5233 07:20:55,670 --> 07:20:54,298 so we wanted to collect lots of 5234 07:20:56,990 --> 07:20:55,680 different evaporites which are these 5235 07:20:59,690 --> 07:20:57,000 salts that are forming around the lake 5236 07:21:02,510 --> 07:20:59,700 shore as well as precipitates within the 5237 07:21:05,810 --> 07:21:02,520 lake these are different fun examples of 5238 07:21:07,430 --> 07:21:05,820 evaporites we collected so in our winter 5239 07:21:10,610 --> 07:21:07,440 trip you get a lot of these salts 5240 07:21:13,310 --> 07:21:10,620 forming on rocks Around the Lake Shores 5241 07:21:14,930 --> 07:21:13,320 around the brine pools in June this is 5242 07:21:16,548 --> 07:21:14,940 an example of a precipitate that formed 5243 07:21:18,048 --> 07:21:16,558 and fell to the bottom of the lake and 5244 07:21:18,948 --> 07:21:18,058 so you can pick it up from under the 5245 07:21:21,890 --> 07:21:18,958 water 5246 07:21:25,310 --> 07:21:21,900 it's a lot of salt mixed in with mud and 5247 07:21:28,190 --> 07:21:25,320 clay and then in September when it's in 5248 07:21:29,810 --> 07:21:28,200 that salt crust phase you can dig into 5249 07:21:31,070 --> 07:21:29,820 the salt crust and take this out and 5250 07:21:32,150 --> 07:21:31,080 that's what the cross section looks like 5251 07:21:34,310 --> 07:21:32,160 so you're getting these very white 5252 07:21:36,948 --> 07:21:34,320 opaque salts on the top that middle 5253 07:21:38,690 --> 07:21:36,958 layer of translucent Natron salt in the 5254 07:21:41,330 --> 07:21:38,700 middle and then a layer of algae right 5255 07:21:43,850 --> 07:21:41,340 above the mud 5256 07:21:45,288 --> 07:21:43,860 we also wanted to collect sediments from 5257 07:21:46,670 --> 07:21:45,298 the lake bottom and so these are 5258 07:21:49,910 --> 07:21:46,680 pictures of us collecting different 5259 07:21:51,590 --> 07:21:49,920 sediment samples with sediment cores we 5260 07:21:54,048 --> 07:21:51,600 did it both around the lake shore as 5261 07:21:55,490 --> 07:21:54,058 well as at the lake bottom and then the 5262 07:21:57,890 --> 07:21:55,500 center picture you see is us taking 5263 07:21:59,690 --> 07:21:57,900 those sudden cores and chopping off 5264 07:22:01,548 --> 07:21:59,700 different depths in order to see how the 5265 07:22:04,430 --> 07:22:01,558 mineralogy changes with depth in the 5266 07:22:08,810 --> 07:22:06,708 so we did a mineralogy analysis with 5267 07:22:10,730 --> 07:22:08,820 x-ray diffraction we used a Booker d8 5268 07:22:12,770 --> 07:22:10,740 powder x-ray diffractometer with a 5269 07:22:15,230 --> 07:22:12,780 copper anode microfocus x-ray source 5270 07:22:16,490 --> 07:22:15,240 which is the microfocus X-ray source is 5271 07:22:17,930 --> 07:22:16,500 really useful when you have very small 5272 07:22:21,110 --> 07:22:17,940 quantities of powder that you're trying 5273 07:22:22,788 --> 07:22:21,120 to analyze and plotus 100K large area 2D 5274 07:22:24,110 --> 07:22:22,798 detector is really helpful when you want 5275 07:22:27,230 --> 07:22:24,120 to increase the resolution of your 5276 07:22:30,230 --> 07:22:28,490 um just a quick note about sample 5277 07:22:31,788 --> 07:22:30,240 preparation we tried to isolate the 5278 07:22:33,650 --> 07:22:31,798 mineral phases visually as much as we 5279 07:22:36,590 --> 07:22:33,660 could from our samples in order to 5280 07:22:38,690 --> 07:22:36,600 simplify the pattern matching grind it 5281 07:22:40,010 --> 07:22:38,700 up really fine you want to have good 5282 07:22:42,110 --> 07:22:40,020 particle statistics for x-ray 5283 07:22:45,948 --> 07:22:42,120 diffraction and then dropping it onto a 5284 07:22:47,510 --> 07:22:45,958 silk zero background sample holder to 5285 07:22:49,910 --> 07:22:47,520 try and get that flat homogeneous 5286 07:22:51,350 --> 07:22:49,920 surface that's so important 5287 07:22:54,230 --> 07:22:51,360 and then for those of you who haven't 5288 07:22:56,570 --> 07:22:54,240 seen xrd Data before this is sort of 5289 07:22:58,368 --> 07:22:56,580 what it looks like uh you've got your 5290 07:23:01,310 --> 07:22:58,378 tooth Theta on the x-axis intensity and 5291 07:23:03,530 --> 07:23:01,320 the y-axis and your observed pattern is 5292 07:23:06,410 --> 07:23:03,540 in blue this is using a software called 5293 07:23:08,150 --> 07:23:06,420 gsas2 which is an open source code for 5294 07:23:10,250 --> 07:23:08,160 xrd analysis 5295 07:23:12,350 --> 07:23:10,260 and then you're trying to match uh 5296 07:23:15,590 --> 07:23:12,360 database database patterns of different 5297 07:23:18,230 --> 07:23:15,600 minerals to this observed pattern and so 5298 07:23:19,490 --> 07:23:18,240 the calculated one pattern that's a 5299 07:23:21,350 --> 07:23:19,500 conglomeration of all the different 5300 07:23:22,910 --> 07:23:21,360 mineral phases we've identified as shown 5301 07:23:24,468 --> 07:23:22,920 in green overlaid on top of that 5302 07:23:27,230 --> 07:23:24,478 observed pattern 5303 07:23:31,010 --> 07:23:27,240 so this is an example of one evaporite 5304 07:23:33,410 --> 07:23:31,020 and one sediment from these Lakes going 5305 07:23:35,030 --> 07:23:33,420 through on this evaporate here we've 5306 07:23:37,310 --> 07:23:35,040 identified multiple different sodium 5307 07:23:38,990 --> 07:23:37,320 carbonate phases so there's a lot of 5308 07:23:40,850 --> 07:23:39,000 thermonitorite which is sodium carbonate 5309 07:23:43,850 --> 07:23:40,860 with one water molecule at the 60 5310 07:23:45,590 --> 07:23:43,860 percent weight percent level and then 5311 07:23:47,930 --> 07:23:45,600 for reference in this sample here the 5312 07:23:49,910 --> 07:23:47,940 thermonitrite is this blue and so each 5313 07:23:51,730 --> 07:23:49,920 mineral you're supposed to you expect to 5314 07:23:54,468 --> 07:23:51,740 see different Peaks and 5315 07:23:55,910 --> 07:23:54,478 the two Theta range and so we're just 5316 07:23:57,830 --> 07:23:55,920 matching those Peaks 5317 07:23:59,690 --> 07:23:57,840 we're also seeing Toronto which is 5318 07:24:02,448 --> 07:23:59,700 another sodium carbonate as well as the 5319 07:24:04,548 --> 07:24:02,458 nardite sodium sulfate halide sodium 5320 07:24:06,650 --> 07:24:04,558 chloride burkite which is a sodium 5321 07:24:08,690 --> 07:24:06,660 carbonate sulfate and acolyte sodium 5322 07:24:10,368 --> 07:24:08,700 bicarbonate so these mineral phases are 5323 07:24:12,670 --> 07:24:10,378 all very common and these evaporates 5324 07:24:15,530 --> 07:24:12,680 we're finding across these Lakes 5325 07:24:18,410 --> 07:24:15,540 while in the sediment we're seeing a lot 5326 07:24:21,048 --> 07:24:18,420 of feldspars like albeitgeite as well as 5327 07:24:24,230 --> 07:24:21,058 the north of Clays in a North eye and 5328 07:24:26,390 --> 07:24:24,240 other samples around the 70 to 20 to 30 5329 07:24:27,770 --> 07:24:26,400 percent range 5330 07:24:29,448 --> 07:24:27,780 um a secondary phase we're seeing a lot 5331 07:24:31,788 --> 07:24:29,458 of in the sediments is Dolomite which is 5332 07:24:32,930 --> 07:24:31,798 that calcium magnesium carbonate and 5333 07:24:34,968 --> 07:24:32,940 that's very important I'll come back to 5334 07:24:37,128 --> 07:24:34,978 that in a moment we're also seeing a lot 5335 07:24:38,750 --> 07:24:37,138 of minor phases like quartz and 5336 07:24:40,128 --> 07:24:38,760 vesuvianite and other things like that 5337 07:24:42,708 --> 07:24:40,138 that are just present in the natural 5338 07:24:44,090 --> 07:24:42,718 soil in the area 5339 07:24:45,350 --> 07:24:44,100 so then you do this a bunch more times 5340 07:24:47,570 --> 07:24:45,360 because you're a graduate student and 5341 07:24:49,490 --> 07:24:47,580 you do a lot of Labor and you take a lot 5342 07:24:51,468 --> 07:24:49,500 of samples 5343 07:24:54,650 --> 07:24:51,478 and this comes together into the 5344 07:24:56,750 --> 07:24:54,660 complete xrd results from the study so 5345 07:24:58,368 --> 07:24:56,760 I've divided this into results for last 5346 07:25:00,230 --> 07:24:58,378 chance Lake as well as good enough Lake 5347 07:25:01,910 --> 07:25:00,240 and then in each respective like the 5348 07:25:03,530 --> 07:25:01,920 sediments and the salts the salts being 5349 07:25:05,868 --> 07:25:03,540 the evaporites around the Lakeshore as 5350 07:25:07,070 --> 07:25:05,878 well as the precipitates and the lake on 5351 07:25:08,150 --> 07:25:07,080 the left hand side we have all the 5352 07:25:09,288 --> 07:25:08,160 different mineral phases we've 5353 07:25:11,990 --> 07:25:09,298 identified 5354 07:25:14,990 --> 07:25:12,000 so in the sediments the main phases of 5355 07:25:16,968 --> 07:25:15,000 Interest were these feldspars both 5356 07:25:20,090 --> 07:25:16,978 plagioclase feldspar as well as Alkali 5357 07:25:22,610 --> 07:25:20,100 or k-feld spars as well as Dolomite 5358 07:25:23,990 --> 07:25:22,620 those calcium carbonates is and Mica the 5359 07:25:25,730 --> 07:25:24,000 clay minerals 5360 07:25:27,410 --> 07:25:25,740 we're also seeing some thermonitrite 5361 07:25:29,330 --> 07:25:27,420 that sodium carbonate and the good 5362 07:25:31,310 --> 07:25:29,340 enough Lake sediments but not in the 5363 07:25:34,010 --> 07:25:31,320 last chance Lake sediments 5364 07:25:35,990 --> 07:25:34,020 and then the main mineral phases we're 5365 07:25:37,368 --> 07:25:36,000 seeing in the evaporites or the salts 5366 07:25:39,288 --> 07:25:37,378 are those sodium carbonates both 5367 07:25:42,770 --> 07:25:39,298 thermonitrite and Trona as well as 5368 07:25:46,010 --> 07:25:42,780 burkite that sodium carbonate sulfate 5369 07:25:47,690 --> 07:25:46,020 a quick word about hydrated minerals we 5370 07:25:49,310 --> 07:25:47,700 only detected thermonitrite which is 5371 07:25:50,990 --> 07:25:49,320 sodium carbonate with one water molecule 5372 07:25:52,010 --> 07:25:51,000 in the xod patterns after sample 5373 07:25:54,590 --> 07:25:52,020 preparation 5374 07:25:56,690 --> 07:25:54,600 however previous studies of this area 5375 07:25:59,150 --> 07:25:56,700 have identified natural salts as the 5376 07:26:01,910 --> 07:25:59,160 predominant phase Natron is just sodium 5377 07:26:03,770 --> 07:26:01,920 carbonate with 10 water molecules and so 5378 07:26:05,868 --> 07:26:03,780 if the relative humidity is below 60 5379 07:26:08,570 --> 07:26:05,878 percent at zero degrees Celsius or 70 5380 07:26:09,770 --> 07:26:08,580 percent at room temperature then Natron 5381 07:26:11,208 --> 07:26:09,780 will lose its water and turn into 5382 07:26:12,650 --> 07:26:11,218 therminatrite and so we're just 5383 07:26:15,110 --> 07:26:12,660 anticipating that's what happened in our 5384 07:26:16,968 --> 07:26:15,120 samples here since the relative humidity 5385 07:26:19,128 --> 07:26:16,978 in indoor environments is around 50 5386 07:26:20,390 --> 07:26:19,138 percent so you can see this plot on the 5387 07:26:22,788 --> 07:26:20,400 right hand side from Haines at all 5388 07:26:24,890 --> 07:26:22,798 showing Natron here turning into 5389 07:26:26,150 --> 07:26:24,900 thermonitrite when you've decreased 5390 07:26:28,788 --> 07:26:26,160 relative humidity and increased 5391 07:26:33,170 --> 07:26:31,070 so in summary we found that the 5392 07:26:34,910 --> 07:26:33,180 evaporites or the salts are dominated by 5393 07:26:36,350 --> 07:26:34,920 sodium carbonates sodium carbonate 5394 07:26:38,030 --> 07:26:36,360 sulfate and sodium chloride 5395 07:26:40,670 --> 07:26:38,040 demonstrating the predominance of that 5396 07:26:42,410 --> 07:26:40,680 sodium ion in The Lakes whereas the 5397 07:26:44,030 --> 07:26:42,420 sediments are dominated by carbonates 5398 07:26:46,850 --> 07:26:44,040 both Dolomite and acry as well as 5399 07:26:50,330 --> 07:26:46,860 feldspars plagioclase and K feldspar 5400 07:26:52,910 --> 07:26:50,340 quartz peroxine and Clay minerals 5401 07:26:54,708 --> 07:26:52,920 however the big takeaway was we found no 5402 07:26:56,690 --> 07:26:54,718 calcium phosphate which is that appetite 5403 07:26:58,968 --> 07:26:56,700 I talked about earlier in any of the 5404 07:27:01,190 --> 07:26:58,978 samples and this was confirmed by icpms 5405 07:27:02,330 --> 07:27:01,200 data showing very low abundance of 5406 07:27:04,548 --> 07:27:02,340 phosphorus and all of the different 5407 07:27:06,288 --> 07:27:04,558 samples we've taken so it's not just an 5408 07:27:08,628 --> 07:27:06,298 xrd fluke it's also backed up by 5409 07:27:10,128 --> 07:27:08,638 Elemental abundances 5410 07:27:12,350 --> 07:27:10,138 um these results are consistent with the 5411 07:27:13,968 --> 07:27:12,360 hypothesis that calcium carbonates 5412 07:27:17,150 --> 07:27:13,978 precipitate early in the mineralization 5413 07:27:19,010 --> 07:27:17,160 sequence of these Lakes thus decreasing 5414 07:27:21,170 --> 07:27:19,020 the dissolved calcium concentrations and 5415 07:27:22,850 --> 07:27:21,180 allowing phosphate to accumulate to high 5416 07:27:25,128 --> 07:27:22,860 concentrations instead of precipitating 5417 07:27:27,288 --> 07:27:25,138 out as appetite which is that calcium 5418 07:27:31,010 --> 07:27:27,298 phosphate 5419 07:27:32,690 --> 07:27:31,020 concentrations in solution and that's 5420 07:27:34,670 --> 07:27:32,700 great for that Prebiotic phosphorylation 5421 07:27:37,070 --> 07:27:34,680 that you need very high phosphate 5422 07:27:40,250 --> 07:27:37,080 concentrations to get that incorporation 5423 07:27:41,510 --> 07:27:40,260 into your nucleotides and the potential 5424 07:27:44,690 --> 07:27:41,520 origin of life so these could be really 5425 07:27:47,030 --> 07:27:44,700 good environments for analogs for hidea 5426 07:27:48,960 --> 07:27:47,040 and Earth Lakes where life started 5427 07:27:55,670 --> 07:27:48,970 and that's it 5428 07:27:57,410 --> 07:27:55,680 [Applause] 5429 07:28:02,208 --> 07:27:57,420 thanks Kimberly we have plenty of time 5430 07:28:06,410 --> 07:28:04,490 I have a quick one for you yeah 5431 07:28:11,570 --> 07:28:06,420 um do you know how good enough Lake was 5432 07:28:11,580 --> 07:28:15,170 tension and when they got 5433 07:28:15,180 --> 07:28:18,708 they got back east 5434 07:28:21,890 --> 07:28:20,030 I was just curious because when we were 5435 07:28:24,490 --> 07:28:21,900 in Australia there was a lot of strange 5436 07:28:27,170 --> 07:28:24,500 Lake names out there like dead kangaroo 5437 07:28:29,330 --> 07:28:27,180 uh Peaks Piggery and we didn't really 5438 07:28:31,430 --> 07:28:29,340 understand like the history of them but 5439 07:28:33,468 --> 07:28:31,440 yeah anyway there were a lot of jokes in 5440 07:28:36,070 --> 07:28:33,478 the field uh about oh it's our last 5441 07:28:47,750 --> 07:28:36,080 chance to get our last chance sample and 5442 07:28:53,448 --> 07:28:50,868 hi I'm Ellie from CU Boulder and I was 5443 07:28:55,548 --> 07:28:53,458 wondering if the so I know you said your 5444 07:28:58,850 --> 07:28:55,558 sediments are a pledge doll Micah and 5445 07:29:00,530 --> 07:28:58,860 feldspar dominated I was curious if you 5446 07:29:02,448 --> 07:29:00,540 would think that the similar pattern 5447 07:29:03,948 --> 07:29:02,458 that you saw here would happen even if 5448 07:29:05,930 --> 07:29:03,958 your soda Lake was hosted by a different 5449 07:29:08,090 --> 07:29:05,940 type of like set like Base Rock 5450 07:29:09,708 --> 07:29:08,100 essentially like if we change instead of 5451 07:29:10,968 --> 07:29:09,718 balsaltic or things like that like do 5452 07:29:12,350 --> 07:29:10,978 you feel like the same pattern would 5453 07:29:13,670 --> 07:29:12,360 hold in terms of the precipitation of 5454 07:29:14,990 --> 07:29:13,680 the evaporites 5455 07:29:16,850 --> 07:29:15,000 yeah 5456 07:29:18,590 --> 07:29:16,860 um these Lakes are very dependent on the 5457 07:29:20,330 --> 07:29:18,600 host mineralogy and so you wouldn't 5458 07:29:22,368 --> 07:29:20,340 expect to see the same 5459 07:29:23,750 --> 07:29:22,378 um aqueous chemistry in a different host 5460 07:29:25,610 --> 07:29:23,760 environment and that's one of the 5461 07:29:27,650 --> 07:29:25,620 reasons why these uh this environment is 5462 07:29:30,288 --> 07:29:27,660 so interesting is because of that uh 5463 07:29:32,090 --> 07:29:30,298 plagi Clays Base Rock causing 5464 07:29:34,910 --> 07:29:32,100 um this very specific aqueous chemistry 5465 07:29:37,610 --> 07:29:34,920 so even just like what is it 100 miles 5466 07:29:39,830 --> 07:29:37,620 nearby is an incredibly sulfate-rich 5467 07:29:43,368 --> 07:29:39,840 Lake that people study for different 5468 07:29:51,410 --> 07:29:43,378 reasons so slight change in geology big 5469 07:29:55,310 --> 07:29:53,810 a really interesting talk uh I have kind 5470 07:29:57,708 --> 07:29:55,320 of two questions 5471 07:30:00,410 --> 07:29:57,718 um you mentioned that you collected 5472 07:30:01,548 --> 07:30:00,420 samples seasonally ended sediment by 5473 07:30:04,670 --> 07:30:01,558 death measurements do you see any 5474 07:30:06,708 --> 07:30:04,680 variability in your mineralization based 5475 07:30:08,810 --> 07:30:06,718 on like seasons and was that reflected 5476 07:30:11,868 --> 07:30:08,820 any depth transect 5477 07:30:14,690 --> 07:30:11,878 yes we hoped we would see more variation 5478 07:30:17,510 --> 07:30:14,700 but we didn't uh the only variation you 5479 07:30:19,250 --> 07:30:17,520 really saw was that you could say and 5480 07:30:21,170 --> 07:30:19,260 maybe this isn't even a statistically 5481 07:30:22,968 --> 07:30:21,180 like significant conclusion is that you 5482 07:30:25,548 --> 07:30:22,978 might see more Dolomite at the top of 5483 07:30:27,230 --> 07:30:25,558 the sediment core so like right in the 5484 07:30:28,730 --> 07:30:27,240 interaction Zone with the water you're 5485 07:30:30,650 --> 07:30:28,740 getting less Dolomite at depth which 5486 07:30:32,628 --> 07:30:30,660 makes sense for calcium carbonate 5487 07:30:34,070 --> 07:30:32,638 precipitating out of solution whereas at 5488 07:30:35,930 --> 07:30:34,080 depth in the sediment cores you're 5489 07:30:38,330 --> 07:30:35,940 getting more of those feldspars which is 5490 07:30:48,910 --> 07:30:38,340 just the host Rock but not as much in 5491 07:30:48,920 --> 07:30:52,788 two slides back 5492 07:31:01,128 --> 07:30:55,548 yeah so like you have data for I think 5493 07:31:03,170 --> 07:31:01,138 uh necklite uh and third nine diet which 5494 07:31:06,170 --> 07:31:03,180 has uncertainty higher than the data so 5495 07:31:07,610 --> 07:31:06,180 is it normal or how can you explain this 5496 07:31:09,708 --> 07:31:07,620 sorry could you say the last part again 5497 07:31:11,628 --> 07:31:09,718 so the uncertainty in the data is higher 5498 07:31:13,548 --> 07:31:11,638 than the the value so can you explain 5499 07:31:16,070 --> 07:31:13,558 this yes because a lot of these samples 5500 07:31:17,510 --> 07:31:16,080 only have these minor phases and a 5501 07:31:18,948 --> 07:31:17,520 couple of the samples 5502 07:31:20,390 --> 07:31:18,958 um and so there's just not very good 5503 07:31:21,410 --> 07:31:20,400 counting statistics we're talking about 5504 07:31:23,510 --> 07:31:21,420 maybe 5505 07:31:26,390 --> 07:31:23,520 three out of 100 samples or something 5506 07:31:29,208 --> 07:31:26,400 that have these minor phases 5507 07:31:31,670 --> 07:31:29,218 um so yeah 5508 07:31:34,610 --> 07:31:31,680 a Taylor plattner at Georgia Institute 5509 07:31:37,548 --> 07:31:34,620 of Technology this was really cool I had 5510 07:31:39,650 --> 07:31:37,558 no idea that these Lakes were so high in 5511 07:31:41,750 --> 07:31:39,660 phosphate um I know a couple of people 5512 07:31:44,510 --> 07:31:41,760 that are have studied like last chance 5513 07:31:45,230 --> 07:31:44,520 Lake and then the basket Lakes 5514 07:31:47,330 --> 07:31:45,240 um 5515 07:31:48,770 --> 07:31:47,340 I was curious 5516 07:31:50,090 --> 07:31:48,780 um because you were saying at the end 5517 07:31:52,670 --> 07:31:50,100 you know 5518 07:31:55,190 --> 07:31:52,680 interesting in terms of like the origin 5519 07:31:56,690 --> 07:31:55,200 of Life have you thought about actually 5520 07:31:58,548 --> 07:31:56,700 I have a couple questions 5521 07:32:01,968 --> 07:31:58,558 um have you thought about 5522 07:32:05,330 --> 07:32:01,978 like looking at what may be preserved in 5523 07:32:07,610 --> 07:32:05,340 in these salts or and I also have a 5524 07:32:10,190 --> 07:32:07,620 question on I know you did xrd do you 5525 07:32:10,788 --> 07:32:10,200 plan on doing any other analyzes 5526 07:32:14,150 --> 07:32:10,798 um 5527 07:32:15,708 --> 07:32:14,160 with your samples yeah so I guess your 5528 07:32:21,468 --> 07:32:15,718 first question about if we're studying 5529 07:32:25,548 --> 07:32:23,330 yeah so 5530 07:32:26,510 --> 07:32:25,558 um out of my macroscopic scale when you 5531 07:32:28,368 --> 07:32:26,520 go there it's really interesting because 5532 07:32:31,070 --> 07:32:28,378 you see all these brine flies that are 5533 07:32:32,628 --> 07:32:31,080 just encrusted in the salt which is kind 5534 07:32:34,788 --> 07:32:32,638 of it's kind of freaky because in the 5535 07:32:36,948 --> 07:32:34,798 summer you're like encompassed by flies 5536 07:32:38,448 --> 07:32:36,958 and then in the winter it's like a fly 5537 07:32:40,910 --> 07:32:38,458 cemetery and there's just a bunch of 5538 07:32:43,850 --> 07:32:40,920 dead flies in the ground but 5539 07:32:49,670 --> 07:32:43,860 um in a more astrobiology sense 5540 07:32:52,250 --> 07:32:49,680 um there are other teams at I think it's 5541 07:32:54,410 --> 07:32:52,260 shoot University in Canada who are 5542 07:32:56,930 --> 07:32:54,420 studying the current microbiology in the 5543 07:32:59,270 --> 07:32:56,940 ice because there are living microbes in 5544 07:33:00,468 --> 07:32:59,280 the ice in the winter and so we're not 5545 07:33:02,448 --> 07:33:00,478 necessarily doing that work but there 5546 07:33:07,368 --> 07:33:02,458 are colleagues who are 5547 07:33:12,468 --> 07:33:10,368 yes okay so uh my section of the work 5548 07:33:14,150 --> 07:33:12,478 was a lot about the mineralogy of the 5549 07:33:15,468 --> 07:33:14,160 sediments and the evaporites but my 5550 07:33:17,390 --> 07:33:15,478 colleagues Sebastian Haas did a lot more 5551 07:33:20,390 --> 07:33:17,400 of the water chemistry 5552 07:33:21,708 --> 07:33:20,400 um and so we're submitting a paper now 5553 07:33:24,468 --> 07:33:21,718 and hopefully you'll be able to read 5554 07:33:27,390 --> 07:33:24,478 that and hear all about his work as well 5555 07:33:33,230 --> 07:33:27,400 thank you very much Kimberly yeah 5556 07:33:36,468 --> 07:33:33,240 [Applause] 5557 07:33:40,010 --> 07:33:36,478 okay our final speaker 5558 07:33:44,448 --> 07:33:40,020 of salty stuff 5559 07:33:52,128 --> 07:33:45,468 oh 5560 07:33:57,350 --> 07:33:54,350 all right 5561 07:33:59,090 --> 07:33:57,360 so uh I'm gonna call back a little bit 5562 07:34:01,788 --> 07:33:59,100 to a couple of the sites that Emily 5563 07:34:03,350 --> 07:34:01,798 mentioned before and uh what's exciting 5564 07:34:04,968 --> 07:34:03,360 for me is that I'm in San Diego for the 5565 07:34:06,770 --> 07:34:04,978 first time so I finally might be able to 5566 07:34:08,270 --> 07:34:06,780 go see one of the field sites I'm about 5567 07:34:10,250 --> 07:34:08,280 to talk about and I had no idea that 5568 07:34:12,830 --> 07:34:10,260 they were actually palm trees down here 5569 07:34:15,890 --> 07:34:12,840 around my supposedly extreme field site 5570 07:34:17,810 --> 07:34:15,900 so that'll be a a funny dichotomy there 5571 07:34:20,330 --> 07:34:17,820 but um so yeah we're gonna be following 5572 07:34:23,510 --> 07:34:20,340 the salt uh and it's going to be a lot 5573 07:34:25,670 --> 07:34:23,520 of salt so uh uh hang tight there 5574 07:34:28,128 --> 07:34:25,680 so the first field site South Bay 5575 07:34:31,730 --> 07:34:28,138 saltworks which is down the road 5576 07:34:35,690 --> 07:34:31,740 um is a salt Farm which as water is 5577 07:34:37,730 --> 07:34:35,700 taken from the bay it is brought in and 5578 07:34:40,490 --> 07:34:37,740 um the the people there are are 5579 07:34:42,590 --> 07:34:40,500 basically taking the the hay light out 5580 07:34:44,330 --> 07:34:42,600 and using that to I believe soften the 5581 07:34:46,548 --> 07:34:44,340 water here and then the magnesium 5582 07:34:48,890 --> 07:34:46,558 chloride also gets concentrated and and 5583 07:34:51,350 --> 07:34:48,900 separated and so you get these 5584 07:34:53,868 --> 07:34:51,360 um these really sodium chloride 5585 07:34:55,368 --> 07:34:53,878 concentrated uh regions and magnesium 5586 07:34:57,410 --> 07:34:55,378 concentrated magnesium chloride 5587 07:34:59,930 --> 07:34:57,420 concentrated regions and then you also 5588 07:35:02,270 --> 07:34:59,940 have uh regions which are a lot more 5589 07:35:03,890 --> 07:35:02,280 like seawater and so 5590 07:35:05,330 --> 07:35:03,900 um that's South Bay salt works that's 5591 07:35:07,368 --> 07:35:05,340 one of the sites I'll be talking about a 5592 07:35:08,270 --> 07:35:07,378 lot today and what we're investigating 5593 07:35:10,490 --> 07:35:08,280 there 5594 07:35:12,830 --> 07:35:10,500 um with oceans across space and time uh 5595 07:35:15,350 --> 07:35:12,840 is can bioseignature molecules be 5596 07:35:18,230 --> 07:35:15,360 detected in these sites um with these 5597 07:35:20,150 --> 07:35:18,240 super high salinities and uh then how 5598 07:35:24,770 --> 07:35:20,160 does that input impact our search for 5599 07:35:26,690 --> 07:35:24,780 life elsewhere and um then how do these 5600 07:35:28,368 --> 07:35:26,700 vary with things like water activity and 5601 07:35:30,530 --> 07:35:28,378 ion concentration 5602 07:35:32,090 --> 07:35:30,540 and then here's another analog site in 5603 07:35:33,530 --> 07:35:32,100 Western Australia this is Lake Campion 5604 07:35:34,670 --> 07:35:33,540 which is a very interesting site that we 5605 07:35:36,830 --> 07:35:34,680 looked at 5606 07:35:40,250 --> 07:35:36,840 um and uh so these are transient lakes 5607 07:35:42,230 --> 07:35:40,260 and so uh they um they evaporate during 5608 07:35:44,208 --> 07:35:42,240 the drier warmer months and then they 5609 07:35:46,010 --> 07:35:44,218 fill up during the winter months and so 5610 07:35:48,890 --> 07:35:46,020 you get these salt crusts which build up 5611 07:35:50,990 --> 07:35:48,900 on the bottom of them and so uh these 5612 07:35:52,850 --> 07:35:51,000 are really interesting because uh the 5613 07:35:54,230 --> 07:35:52,860 the evaporation process is happening 5614 07:35:55,250 --> 07:35:54,240 very actively so we can get a modern 5615 07:35:57,530 --> 07:35:55,260 look 5616 07:35:58,968 --> 07:35:57,540 um at what's happening there and so in 5617 07:36:00,890 --> 07:35:58,978 general analog sites can give us 5618 07:36:02,990 --> 07:36:00,900 training grounds for robotic exploration 5619 07:36:05,628 --> 07:36:03,000 on other planets they can help us test 5620 07:36:09,350 --> 07:36:05,638 our instruments and uh particularly we 5621 07:36:13,250 --> 07:36:09,360 want to know how salt and acid acidic uh 5622 07:36:15,468 --> 07:36:13,260 um low PH environments affect our uh our 5623 07:36:17,510 --> 07:36:15,478 instruments and then it can give us 5624 07:36:19,730 --> 07:36:17,520 insight into the environmental processes 5625 07:36:22,910 --> 07:36:19,740 and the biology happening there 5626 07:36:25,490 --> 07:36:22,920 and so uh now I'm going to uh shout out 5627 07:36:26,930 --> 07:36:25,500 uh Luke Fisher's review paper in 5628 07:36:28,490 --> 07:36:26,940 environmental microbiology where he 5629 07:36:31,070 --> 07:36:28,500 talks all about the bioseignature 5630 07:36:32,990 --> 07:36:31,080 preservation in brines particularly in 5631 07:36:35,208 --> 07:36:33,000 deep hyper saline anoxic basins which I 5632 07:36:36,830 --> 07:36:35,218 won't be talking about today but when it 5633 07:36:39,110 --> 07:36:36,840 comes to brines themselves as opposed to 5634 07:36:41,990 --> 07:36:39,120 evaporates or salt crystals 5635 07:36:44,570 --> 07:36:42,000 um we know that DNA and RNA are well 5636 07:36:47,510 --> 07:36:44,580 preserved while mRNA is not as well 5637 07:36:49,910 --> 07:36:47,520 preserved and that ATP preservation has 5638 07:36:51,530 --> 07:36:49,920 been observed by uh to ovala at all in 5639 07:36:54,230 --> 07:36:51,540 1987. 5640 07:36:57,350 --> 07:36:54,240 um but not much has been done about that 5641 07:36:59,510 --> 07:36:57,360 since then and lipid preservation is 5642 07:37:01,070 --> 07:36:59,520 being studied more and more recently and 5643 07:37:03,170 --> 07:37:01,080 so that's good but but these aren't 5644 07:37:03,770 --> 07:37:03,180 nearly as well explored 5645 07:37:07,490 --> 07:37:03,780 um 5646 07:37:08,868 --> 07:37:07,500 as genetic uh compounds and so uh one 5647 07:37:10,788 --> 07:37:08,878 compound that we're looking at ATP 5648 07:37:13,430 --> 07:37:10,798 adenosine triphosphate it's a 5649 07:37:16,788 --> 07:37:13,440 short-lived molecule and it's used in 5650 07:37:18,770 --> 07:37:16,798 astrobiology and in ecology as a marker 5651 07:37:20,448 --> 07:37:18,780 of microbial activity and so if you have 5652 07:37:21,948 --> 07:37:20,458 a lot of ATP means that a lot of 5653 07:37:24,230 --> 07:37:21,958 microbial activity is happening if you 5654 07:37:25,368 --> 07:37:24,240 don't have any microbial activity then 5655 07:37:28,610 --> 07:37:25,378 you're probably not going to have much 5656 07:37:31,850 --> 07:37:28,620 ATP but it's very highly evolved so as a 5657 07:37:33,830 --> 07:37:31,860 biosignature it might be less agnostic 5658 07:37:35,810 --> 07:37:33,840 than for example amino acids and so we 5659 07:37:38,448 --> 07:37:35,820 could look at polypeptides or we could 5660 07:37:41,030 --> 07:37:38,458 look at individual amino acids and we 5661 07:37:43,670 --> 07:37:41,040 target biological amino acids in this 5662 07:37:46,190 --> 07:37:43,680 study as well as osmolite amino acids 5663 07:37:47,868 --> 07:37:46,200 which are solute compounds that are 5664 07:37:52,430 --> 07:37:47,878 accumulated by microbes when they're 5665 07:37:54,890 --> 07:37:52,440 under high stress in hyper saline sites 5666 07:37:56,150 --> 07:37:54,900 yeah so and that's well understood in 5667 07:37:57,708 --> 07:37:56,160 the literature that these osmolites 5668 07:37:59,628 --> 07:37:57,718 exist 5669 07:38:01,788 --> 07:37:59,638 and so first I'll talk about the methods 5670 07:38:03,830 --> 07:38:01,798 that we used in in the field 5671 07:38:06,830 --> 07:38:03,840 um or near the field in the motel room 5672 07:38:08,570 --> 07:38:06,840 we uh looked for ATP using a luciferase 5673 07:38:11,510 --> 07:38:08,580 assay and so say you have a beautiful 5674 07:38:13,670 --> 07:38:11,520 Crystal uh uh from the crust of a lake 5675 07:38:15,230 --> 07:38:13,680 like this from Western Australia then 5676 07:38:18,288 --> 07:38:15,240 you take it to your Western Australia 5677 07:38:20,628 --> 07:38:18,298 motel room and you do a uh you set out 5678 07:38:23,868 --> 07:38:20,638 your samples we weigh them out we 5679 07:38:26,690 --> 07:38:23,878 extract them in hot water and then we 5680 07:38:28,730 --> 07:38:26,700 add our luciferase and luciferin and we 5681 07:38:30,830 --> 07:38:28,740 have a field portable luminometer in 5682 07:38:34,430 --> 07:38:30,840 order to do our analyzes 5683 07:38:36,770 --> 07:38:34,440 and so that's how we uh quantify ATP 5684 07:38:39,230 --> 07:38:36,780 and moving on to what we do at Georgia 5685 07:38:41,570 --> 07:38:39,240 Tech when we bring the samples home so 5686 07:38:43,250 --> 07:38:41,580 uh I was so glad to hear that uh another 5687 07:38:44,750 --> 07:38:43,260 uh person here was using capillary 5688 07:38:47,090 --> 07:38:44,760 electrophoresis so I don't need to 5689 07:38:49,010 --> 07:38:47,100 explain it in its entirety again but um 5690 07:38:50,390 --> 07:38:49,020 it's a separation method that uh in our 5691 07:38:52,368 --> 07:38:50,400 lab we pair with laser-induced 5692 07:38:53,990 --> 07:38:52,378 fluorescence and so laser-induced 5693 07:38:56,330 --> 07:38:54,000 fluorescence mean means that we're 5694 07:38:59,090 --> 07:38:56,340 tagging our amino acids our compounds of 5695 07:39:01,548 --> 07:38:59,100 Interest with a fluorescent dye so we're 5696 07:39:03,708 --> 07:39:01,558 targeting specific compounds 5697 07:39:05,208 --> 07:39:03,718 um and so this is a targeted technique 5698 07:39:08,510 --> 07:39:05,218 which has very low limits of detection 5699 07:39:11,750 --> 07:39:08,520 and very high sensitivity and so 5700 07:39:13,128 --> 07:39:11,760 um we did this at South Bay saltworks on 5701 07:39:15,948 --> 07:39:13,138 one of the samples that has a water 5702 07:39:18,110 --> 07:39:15,958 activity of below 0.4 and magnesium 5703 07:39:20,448 --> 07:39:18,120 concentration of more than four molar 5704 07:39:23,090 --> 07:39:20,458 and uh this is only a one to ten 5705 07:39:26,570 --> 07:39:23,100 dilution so using a method that 5706 07:39:29,868 --> 07:39:26,580 um Marshall Seton and I developed uh we 5707 07:39:32,510 --> 07:39:29,878 got the concentration of amino acids in 5708 07:39:34,430 --> 07:39:32,520 this sample down to tens of nanomolar 5709 07:39:36,410 --> 07:39:34,440 the limits of detection for this method 5710 07:39:38,330 --> 07:39:36,420 General are in the tense of picomolar 5711 07:39:39,650 --> 07:39:38,340 and we did this using a commercial 5712 07:39:40,250 --> 07:39:39,660 instrument 5713 07:39:41,930 --> 07:39:40,260 um 5714 07:39:44,628 --> 07:39:41,940 and again it was only a one to ten 5715 07:39:46,610 --> 07:39:44,638 dilution for this uh hyper saline uh 5716 07:39:48,770 --> 07:39:46,620 sample so we were delighted that uh the 5717 07:39:51,410 --> 07:39:48,780 results came out like this and then for 5718 07:39:53,750 --> 07:39:51,420 an untargeted analysis we can use uh 5719 07:39:55,610 --> 07:39:53,760 microchip capillary electrophoresis 5720 07:39:58,610 --> 07:39:55,620 paired with uh high resolution Mass 5721 07:40:00,230 --> 07:39:58,620 spectrometry so if we take the same 5722 07:40:02,330 --> 07:40:00,240 sample and we look at it using an 5723 07:40:05,390 --> 07:40:02,340 untargeted method where we can get the 5724 07:40:07,788 --> 07:40:05,400 master charge ratio of the compounds 5725 07:40:09,530 --> 07:40:07,798 that we're interested in then uh 5726 07:40:13,310 --> 07:40:09,540 combining the zip chip commercial setup 5727 07:40:14,628 --> 07:40:13,320 with a thermal Q exactive orbitrap we 5728 07:40:18,530 --> 07:40:14,638 this is what the chip looks like it's 5729 07:40:20,990 --> 07:40:18,540 very cute uh we get a very interesting 5730 07:40:24,110 --> 07:40:21,000 set of compounds which we didn't 5731 07:40:27,110 --> 07:40:24,120 necessarily Target and so 5732 07:40:29,810 --> 07:40:27,120 uh moving back to the LIF analyzes for 5733 07:40:31,490 --> 07:40:29,820 the results what we first observed was 5734 07:40:33,530 --> 07:40:31,500 that as we increase in magnesium 5735 07:40:35,750 --> 07:40:33,540 concentration and decrease in water 5736 07:40:38,930 --> 07:40:35,760 activity and increase in chaotropicity 5737 07:40:41,448 --> 07:40:38,940 we get a significant increase in the 5738 07:40:43,730 --> 07:40:41,458 dissolved free primary amines that we 5739 07:40:45,230 --> 07:40:43,740 were targeting and so that would be our 5740 07:40:48,110 --> 07:40:45,240 biological amino acids which you've 5741 07:40:49,968 --> 07:40:48,120 identified here and as you go up you 5742 07:40:52,310 --> 07:40:49,978 have higher magnesium sites and we have 5743 07:40:54,110 --> 07:40:52,320 a lot higher Peaks and we also have a 5744 07:40:57,468 --> 07:40:54,120 lot higher values for Quantified amino 5745 07:41:00,170 --> 07:40:57,478 acids and so we attribute this to evapo 5746 07:41:01,490 --> 07:41:00,180 concentration as the sites which have a 5747 07:41:03,048 --> 07:41:01,500 lot of water and a lot of salt and then 5748 07:41:04,850 --> 07:41:03,058 evaporate and leave the salts and the 5749 07:41:07,070 --> 07:41:04,860 Organics behind the concentration is 5750 07:41:09,468 --> 07:41:07,080 higher so that's pretty straightforward 5751 07:41:11,628 --> 07:41:09,478 and simple but it is very useful in the 5752 07:41:14,150 --> 07:41:11,638 case where we're looking at very low 5753 07:41:17,090 --> 07:41:14,160 biomass regions so 5754 07:41:19,368 --> 07:41:17,100 next we then put it in micro microchip 5755 07:41:21,530 --> 07:41:19,378 cems and we looked for these same 5756 07:41:23,990 --> 07:41:21,540 compounds and we found a lot of them 5757 07:41:26,628 --> 07:41:24,000 there and so you can see histidine 5758 07:41:29,030 --> 07:41:26,638 Glycine alanine isoleucine and leucine 5759 07:41:32,030 --> 07:41:29,040 are resolved there serine 5760 07:41:34,010 --> 07:41:32,040 Etc et cetera glutamic and aspartic acid 5761 07:41:35,868 --> 07:41:34,020 um and this was only a one to four 5762 07:41:37,128 --> 07:41:35,878 dilution of that same sample so we were 5763 07:41:40,010 --> 07:41:37,138 really delighted by these results as 5764 07:41:42,110 --> 07:41:40,020 well and in the same separation just um 5765 07:41:45,230 --> 07:41:42,120 looking at different traces different M 5766 07:41:48,288 --> 07:41:45,240 over Z's we see a couple polypeptides 5767 07:41:51,110 --> 07:41:48,298 and we see some adenine and guanidine in 5768 07:41:52,850 --> 07:41:51,120 there as well uh and so these are things 5769 07:41:54,830 --> 07:41:52,860 that we didn't necessarily look for in 5770 07:41:56,868 --> 07:41:54,840 the celif but now that we're combining 5771 07:41:58,128 --> 07:41:56,878 it with an untargeted method we can we 5772 07:42:00,110 --> 07:41:58,138 can get a look at some more compounds 5773 07:42:02,208 --> 07:42:00,120 that we didn't necessarily expect 5774 07:42:04,128 --> 07:42:02,218 and then also osmolites which we did 5775 07:42:05,990 --> 07:42:04,138 expect and did want to look for we found 5776 07:42:09,230 --> 07:42:06,000 those like ornithine sarcasine and 5777 07:42:10,788 --> 07:42:09,240 betaine in our samples with very high 5778 07:42:13,128 --> 07:42:10,798 salt stress being applied to any of the 5779 07:42:15,410 --> 07:42:13,138 microbes that were alive there 5780 07:42:17,208 --> 07:42:15,420 um and and so these are are there in 5781 07:42:19,850 --> 07:42:17,218 significant quantity 5782 07:42:21,170 --> 07:42:19,860 and in Western Australia uh briefly I'll 5783 07:42:23,448 --> 07:42:21,180 just show you some preliminary results 5784 07:42:25,430 --> 07:42:23,458 this is Lake Brown which has a sodium 5785 07:42:29,090 --> 07:42:25,440 concentration of near five molar and a 5786 07:42:30,770 --> 07:42:29,100 water activity of 0.89 so not nearly as 5787 07:42:32,750 --> 07:42:30,780 low water activity as the South Bay 5788 07:42:34,070 --> 07:42:32,760 saltwork sample I just showed you 5789 07:42:35,810 --> 07:42:34,080 um but it has high relative 5790 07:42:37,788 --> 07:42:35,820 concentrations of a lot of these 5791 07:42:41,510 --> 07:42:37,798 compounds including the osmolite 5792 07:42:43,010 --> 07:42:41,520 compound baiting and some lower 5793 07:42:45,110 --> 07:42:43,020 concentrations of other compounds 5794 07:42:47,990 --> 07:42:45,120 including a polypeptide 5795 07:42:50,570 --> 07:42:48,000 and then conversely at Lake Gunter which 5796 07:42:53,390 --> 07:42:50,580 has a higher water activity and a lower 5797 07:42:55,490 --> 07:42:53,400 sodium concentration we see that there 5798 07:42:57,230 --> 07:42:55,500 really isn't any easy way to detect 5799 07:42:58,548 --> 07:42:57,240 those organic compounds with with the 5800 07:43:00,890 --> 07:42:58,558 method that we're using right now so 5801 07:43:03,288 --> 07:43:00,900 just diluting these samples so perhaps 5802 07:43:04,430 --> 07:43:03,298 this indicates that the uh and of course 5803 07:43:06,468 --> 07:43:04,440 there's only two data points with 5804 07:43:07,788 --> 07:43:06,478 Western Australia but you know looking 5805 07:43:09,830 --> 07:43:07,798 at the what we found at South Bay 5806 07:43:11,930 --> 07:43:09,840 saltworks perhaps these saltier sites 5807 07:43:13,788 --> 07:43:11,940 are actually places where it might be 5808 07:43:15,350 --> 07:43:13,798 easier to detect biomolecules because of 5809 07:43:18,368 --> 07:43:15,360 evapo concentration 5810 07:43:20,690 --> 07:43:18,378 and we also want to look at the 5811 07:43:23,030 --> 07:43:20,700 normalized abundance of certain amino 5812 07:43:25,368 --> 07:43:23,040 acids just to see what sort of patterns 5813 07:43:27,530 --> 07:43:25,378 we could find and if we have water 5814 07:43:30,288 --> 07:43:27,540 activity increasing from left to right 5815 07:43:32,150 --> 07:43:30,298 here with the Magnesium sites here we 5816 07:43:35,090 --> 07:43:32,160 see that certain amino acids are upright 5817 07:43:37,910 --> 07:43:35,100 regulated in this magnesium heavy site 5818 07:43:40,430 --> 07:43:37,920 and others are down regulated 5819 07:43:43,430 --> 07:43:40,440 and with that information we decided 5820 07:43:46,070 --> 07:43:43,440 maybe we could classify our sites based 5821 07:43:48,110 --> 07:43:46,080 on the amino acid distribution so if you 5822 07:43:50,030 --> 07:43:48,120 take the distribution in you put in a 5823 07:43:52,548 --> 07:43:50,040 classifier either logistic regression or 5824 07:43:54,288 --> 07:43:52,558 random Forest you could get out one of 5825 07:43:56,150 --> 07:43:54,298 these three different site types and 5826 07:43:57,890 --> 07:43:56,160 this is a small data set and more of a 5827 07:43:59,570 --> 07:43:57,900 proof of concept than anything but it's 5828 07:44:01,788 --> 07:43:59,580 interesting to see that we have a very 5829 07:44:05,090 --> 07:44:01,798 good area under the curve of you know 1 5830 07:44:06,948 --> 07:44:05,100 or 0.83 which uh and and we also can see 5831 07:44:09,590 --> 07:44:06,958 which compounds are driving that the 5832 07:44:11,930 --> 07:44:09,600 most and so that's an interesting thing 5833 07:44:13,730 --> 07:44:11,940 to take note of that might be used in 5834 07:44:14,868 --> 07:44:13,740 the future if we have much larger data 5835 07:44:16,548 --> 07:44:14,878 sets 5836 07:44:20,570 --> 07:44:16,558 and so the last thing I wanted to talk 5837 07:44:22,430 --> 07:44:20,580 about ATP if you remember so uh on the 5838 07:44:24,468 --> 07:44:22,440 x-axis here's a magnesium concentration 5839 07:44:26,150 --> 07:44:24,478 and then we have three y axes because 5840 07:44:28,190 --> 07:44:26,160 why not and 5841 07:44:30,468 --> 07:44:28,200 um uh first of all I want to mention the 5842 07:44:33,288 --> 07:44:30,478 cell counts by microscopy which is uh 5843 07:44:35,690 --> 07:44:33,298 from Ben klempe uh showed that the 5844 07:44:37,190 --> 07:44:35,700 number of active cells in these sites go 5845 07:44:39,410 --> 07:44:37,200 down as you get to the super high 5846 07:44:40,310 --> 07:44:39,420 magnesium concentration regions which is 5847 07:44:42,530 --> 07:44:40,320 also 5848 07:44:46,070 --> 07:44:42,540 um what Emily showed in her talk and so 5849 07:44:48,530 --> 07:44:46,080 uh what we then can look at is the ATP 5850 07:44:52,190 --> 07:44:48,540 concentration which strangely goes up 5851 07:44:54,230 --> 07:44:52,200 even as the concentration of active 5852 07:44:56,090 --> 07:44:54,240 cells goes down and the expected 5853 07:44:58,910 --> 07:44:56,100 activity goes down and so we wondered 5854 07:45:01,490 --> 07:44:58,920 why is that happening because 5855 07:45:02,930 --> 07:45:01,500 um as we know the amino acids are 5856 07:45:04,490 --> 07:45:02,940 concentrating but amino acids don't 5857 07:45:06,830 --> 07:45:04,500 Decay on really short time scales 5858 07:45:10,368 --> 07:45:06,840 they're not broken up by hydrolysis or 5859 07:45:12,590 --> 07:45:10,378 by atpase enzymes but 5860 07:45:14,208 --> 07:45:12,600 we think is that something must be 5861 07:45:18,948 --> 07:45:14,218 driving this and if it's not of Apple 5862 07:45:20,930 --> 07:45:18,958 concentration uh well uh we're wondering 5863 07:45:25,070 --> 07:45:20,940 you know since the ATP hydrolysis rate 5864 07:45:27,770 --> 07:45:25,080 is uh much quicker than the evapo 5865 07:45:29,270 --> 07:45:27,780 concentration rate uh why would the ATP 5866 07:45:31,250 --> 07:45:29,280 accumulate doesn't really make much 5867 07:45:33,890 --> 07:45:31,260 sense but perhaps 5868 07:45:35,868 --> 07:45:33,900 it's being preserved so this to ovala at 5869 07:45:38,810 --> 07:45:35,878 all paper from 1987 that I mentioned way 5870 07:45:41,930 --> 07:45:38,820 earlier uh they found that ATP was 5871 07:45:44,390 --> 07:45:41,940 preserved in low water activity sites 5872 07:45:46,968 --> 07:45:44,400 and so that could be preventing the 5873 07:45:49,670 --> 07:45:46,978 enzymatic uh and natural hydrolysis of 5874 07:45:52,968 --> 07:45:49,680 ATP leaving it to uh persist in the 5875 07:45:54,770 --> 07:45:52,978 solution and additionally it could also 5876 07:45:56,868 --> 07:45:54,780 be used as an osmolite compound as well 5877 07:45:59,270 --> 07:45:56,878 and be accumulated by those 5878 07:46:02,208 --> 07:45:59,280 microorganisms before they end up in a 5879 07:46:03,948 --> 07:46:02,218 super high magnesium site and not very 5880 07:46:06,830 --> 07:46:03,958 active themselves 5881 07:46:09,830 --> 07:46:06,840 so in conclusion we can detect 5882 07:46:12,110 --> 07:46:09,840 biosignatures at micromolar 5883 07:46:15,770 --> 07:46:12,120 concentrations in near saturation brines 5884 07:46:18,230 --> 07:46:15,780 using celif and microce Ms 5885 07:46:19,968 --> 07:46:18,240 and amino acid distribution ratios can 5886 07:46:21,048 --> 07:46:19,978 be well classified based on their brine 5887 07:46:23,570 --> 07:46:21,058 type 5888 07:46:25,368 --> 07:46:23,580 and osmolites are present and detectable 5889 07:46:27,708 --> 07:46:25,378 in some but not all of the South Bay 5890 07:46:29,930 --> 07:46:27,718 saltworks in Western Australia Brines 5891 07:46:32,750 --> 07:46:29,940 and we found preservation of ATP at 5892 07:46:35,270 --> 07:46:32,760 South Bay saltworks and so 5893 07:46:37,070 --> 07:46:35,280 um basically my argument is then why 5894 07:46:38,510 --> 07:46:37,080 don't we follow the salt and see if we 5895 07:46:41,450 --> 07:46:38,520 can find biosignatures there on other 5896 07:46:47,448 --> 07:46:41,460 worlds so thanks for listening 5897 07:46:49,430 --> 07:46:47,458 [Applause] 5898 07:47:01,250 --> 07:46:49,440 thank you Chad we have time for two 5899 07:47:05,868 --> 07:47:03,468 Chad thank you for the talk um that was 5900 07:47:08,810 --> 07:47:05,878 a beautiful separation that you showed 5901 07:47:12,530 --> 07:47:08,820 uh showed earlier and so I'm I'm curious 5902 07:47:16,430 --> 07:47:12,540 uh you did a connotation of amino acids 5903 07:47:20,330 --> 07:47:16,440 using celf method and it looks like 5904 07:47:22,090 --> 07:47:20,340 you've done some work using cems have 5905 07:47:26,510 --> 07:47:22,100 you tried uh 5906 07:47:29,750 --> 07:47:26,520 quantifying the amino acid content in 5907 07:47:31,610 --> 07:47:29,760 the same sites using microchip cems and 5908 07:47:33,530 --> 07:47:31,620 seeing what those look like to try and 5909 07:47:34,968 --> 07:47:33,540 like cross validate both methods and the 5910 07:47:37,010 --> 07:47:34,978 using the same sample yet or have you 5911 07:47:39,708 --> 07:47:37,020 not got to that yet nope so we just 5912 07:47:42,288 --> 07:47:39,718 started doing the micro CMS work over 5913 07:47:44,390 --> 07:47:42,298 the past month and so we're really happy 5914 07:47:46,490 --> 07:47:44,400 how it's been doing with qualitative 5915 07:47:48,410 --> 07:47:46,500 untargeted work but we haven't gone into 5916 07:47:49,448 --> 07:47:48,420 quantitative because the ion suppression 5917 07:47:52,190 --> 07:47:49,458 effects 5918 07:47:53,690 --> 07:47:52,200 might be a bit of a challenge to 5919 07:47:55,310 --> 07:47:53,700 overcome so that'll probably be a little 5920 07:47:56,930 --> 07:47:55,320 bit of a longer project what we have 5921 07:48:00,048 --> 07:47:56,940 done to try to corroborate the amino 5922 07:48:02,390 --> 07:48:00,058 acid concentrations is look at the 5923 07:48:04,610 --> 07:48:02,400 expression of um or not the expression 5924 07:48:08,810 --> 07:48:04,620 rather but the presence of certain 5925 07:48:10,968 --> 07:48:08,820 proteins in the genetic code of the 5926 07:48:13,968 --> 07:48:10,978 microbes that are were found to be 5927 07:48:16,128 --> 07:48:13,978 present here by other uh host 5928 07:48:16,730 --> 07:48:16,138 collaborators and 5929 07:48:19,070 --> 07:48:16,740 um 5930 07:48:20,750 --> 07:48:19,080 we find a moderate correlation between 5931 07:48:23,270 --> 07:48:20,760 the amino acids we see and the amino 5932 07:48:25,010 --> 07:48:23,280 acids that they see but since we don't 5933 07:48:26,810 --> 07:48:25,020 have transcriptomes from all these sites 5934 07:48:28,548 --> 07:48:26,820 we don't know exactly what proteins are 5935 07:48:31,448 --> 07:48:28,558 being made and so I think that's the 5936 07:48:33,468 --> 07:48:31,458 next step is is to connect those from 5937 07:48:35,990 --> 07:48:33,478 metabolomics to transcriptomics to 5938 07:48:43,250 --> 07:48:36,000 genomics just as the talk last night uh 5939 07:48:43,260 --> 07:48:54,288 any last question for Chad 5940 07:48:58,250 --> 07:48:56,090 um I have a two question actually oh 5941 07:49:01,310 --> 07:48:58,260 maybe I didn't really catch you what's a 5942 07:49:03,170 --> 07:49:01,320 pH of the site that you show the 5943 07:49:05,208 --> 07:49:03,180 Magnesium concentration is more than 5944 07:49:06,590 --> 07:49:05,218 four molar that's a great question I 5945 07:49:07,850 --> 07:49:06,600 don't know off the top of my head but I 5946 07:49:09,230 --> 07:49:07,860 can get back to you in a moment yeah 5947 07:49:11,750 --> 07:49:09,240 okay 5948 07:49:13,510 --> 07:49:11,760 um and also how would you determine your 5949 07:49:16,250 --> 07:49:13,520 atp's 5950 07:49:19,430 --> 07:49:16,260 accumulated or protected under high 5951 07:49:22,368 --> 07:49:19,440 selling water or like low water activity 5952 07:49:25,930 --> 07:49:22,378 how did I sorry say again how did I how 5953 07:49:28,610 --> 07:49:25,940 do you know that your ATP non-hydrolysis 5954 07:49:31,250 --> 07:49:28,620 so yeah I don't know that it's not 5955 07:49:33,590 --> 07:49:31,260 hydrolyzed necessarily but I am 5956 07:49:37,070 --> 07:49:33,600 predicting that so the the typical 5957 07:49:38,330 --> 07:49:37,080 destruction method of ATP uh either in 5958 07:49:40,730 --> 07:49:38,340 the cell or in the environment is 5959 07:49:44,570 --> 07:49:40,740 through hydrolysis either performed by 5960 07:49:47,030 --> 07:49:44,580 proteins or just um happening naturally 5961 07:49:49,548 --> 07:49:47,040 in the environment with water and so 5962 07:49:53,090 --> 07:49:49,558 those are the those are the things that 5963 07:49:54,110 --> 07:49:53,100 must uh from what I'm observing have 5964 07:49:57,468 --> 07:49:54,120 been stopped 5965 07:50:00,048 --> 07:49:57,478 if the ATP is going to persist so long 5966 07:50:01,368 --> 07:50:00,058 for it to be evapo concentrated to those 5967 07:50:03,770 --> 07:50:01,378 high of levels 5968 07:50:06,048 --> 07:50:03,780 um the huge Spike there likely wouldn't 5969 07:50:09,110 --> 07:50:06,058 have been possible if of Apple 5970 07:50:12,230 --> 07:50:09,120 concentration weren't a component and so 5971 07:50:15,230 --> 07:50:12,240 um you know unless uh the uh the 5972 07:50:17,388 --> 07:50:15,240 osmolite effect is is uh so much more 5973 07:50:19,190 --> 07:50:17,398 significant than I had thought 5974 07:50:21,948 --> 07:50:19,200 um that could be another reason but I 5975 07:50:25,250 --> 07:50:21,958 still think that uh the the preservation 5976 07:50:28,610 --> 07:50:25,260 of ATP is yeah is linked to the the lack 5977 07:50:31,670 --> 07:50:28,620 of a um a rapid breakdown mechanism uh 5978 07:50:32,650 --> 07:50:31,680 have you ever considered that ATP with 5979 07:50:35,510 --> 07:50:32,660 um 5980 07:50:37,610 --> 07:50:35,520 form some nanostructures to make the 5981 07:50:40,010 --> 07:50:37,620 things happen yeah so whether it 5982 07:50:43,190 --> 07:50:40,020 stabilizes it in some way the yeah so 5983 07:50:44,690 --> 07:50:43,200 I've I don't honestly know much about 5984 07:50:46,430 --> 07:50:44,700 how it would investigate that I've 5985 07:50:48,530 --> 07:50:46,440 spoken to someone recently about um 5986 07:50:52,310 --> 07:50:48,540 potentially modeling it uh using 5987 07:50:54,650 --> 07:50:52,320 molecular Dynamics but uh I haven't you 5988 07:50:56,388 --> 07:50:54,660 know waded into the um you know the 5989 07:50:58,548 --> 07:50:56,398 actual uh 5990 07:50:59,750 --> 07:50:58,558 the structural chemistry of whether of 5991 07:51:01,850 --> 07:50:59,760 whether that would happen but if you 5992 07:51:07,610 --> 07:51:01,860 have any ideas I'd love to hear so 5993 07:51:07,620 --> 07:51:10,670 foreign 5994 07:51:13,548 --> 07:51:12,770 okay so that concludes all the talks for 5995 07:51:16,190 --> 07:51:13,558 today 5996 07:51:17,448 --> 07:51:16,200 um we have a extended poster session so 5997 07:51:18,708 --> 07:51:17,458 it's a little bit longer than the others 5998 07:51:20,690 --> 07:51:18,718 because we have some excellent local 5999 07:51:23,570 --> 07:51:20,700 undergrads that you'll find outside in 6000 07:51:25,548 --> 07:51:23,580 the back patio and thanks to a group at 6001 07:51:27,948 --> 07:51:25,558 upper campus the cosmic tours we have an 6002 07:51:30,948 --> 07:51:27,958 indoor planetarium that's a few doors 6003 07:51:32,930 --> 07:51:30,958 down Miguel just posted a little map of 6004 07:51:34,310 --> 07:51:32,940 where it is so we encourage you like 6005 07:51:36,170 --> 07:51:34,320 throughout the poster session see if you 6006 07:51:38,510 --> 07:51:36,180 can get in there I think it's about a 20 6007 07:51:39,770 --> 07:51:38,520 minute tour or so 6008 07:51:41,388 --> 07:51:39,780 um and besides that we're all going to 6009 07:51:43,070 --> 07:51:41,398 meet at Shore Rider at seven o'clock 6010 07:51:44,930 --> 07:51:43,080 that's when we'll start serving dinner 6011 07:51:46,910 --> 07:51:44,940 and then trivia will start right at 6012 07:51:48,350 --> 07:51:46,920 eight so just feel free to relax the 6013 07:51:50,330 --> 07:51:48,360 hotel or something before 6014 07:51:51,770 --> 07:51:50,340 and then let Miguel or I know if you 6015 07:51:57,320 --> 07:51:51,780 have any any questions or concerns 6016 07:52:28,910 --> 07:52:20,860 [Music]