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yay okay sorry I can't be there I am a

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postdoc at Georgia Tech and I have

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research obligations um but I was able

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to pry myself away from my busy schedule

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for 15 minute warm-up talk which

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probably won't take 15 minutes um son

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Samantha for those of you who don't know

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me and I am predominantly a

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microbiologist but today I'm going to be

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trying to describe to you a very basic

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general concepts and molecular biology

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which lead up to understanding some of

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the researchers that are talking about

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prebiotic chemistry so for all you non

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biologists this one is for you and I

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will try to keep it simple so life what

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is it all about on this planet well from

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a bacteriologist point of view such as

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myself focusing on there for bacterial

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life produces a number of things for us

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such as oxygen I like to breathe you

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like to breathe and we breathe oxygen

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due to bacteria bacteria also are

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involved in all of the major nutrient

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cycles on the planet including the

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nitrogen cycle they make complex carbon

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structures which allow for higher

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organisms to exist such as plants and

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animals and in general they are just

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amazing little bugs but how do they do

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all this how do they do all of these

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mechanisms and pathways well they have

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this informational code which is

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hundreds of millions of years old and

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it's been passed down from one cell to

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another and this code is DNA and I'm

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sure most of you have heard of DNA but

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it's the informational string of life

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and I like to kind of convey it to you

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as a string especially for those non

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biochemist and non biologists in the

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room so there's a string and it has four

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bases I mean by mean cytosine and

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guanine don't worry i will go to much

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more into them other than that but these

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strings are bonded in a ribose sugar

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backbone

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and two units of a phospho sugar

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backbone with their little basis come

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together and they form a secondary

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structure the double helix and I'm sure

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everybody knows the story of the double

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helix so from the double helix which is

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the secondary structure of DNA can come

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and form tertiary structures and

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quaternary structures and all these very

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complicated things but essentially all

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this is is a way to compact the large

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and oftentimes read its code into a

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smaller structure but I'm not going to

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go further into detail than that so how

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does this information become functional

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in the cell if it's in this code and you

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don't want to really perturb this code

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too much how does the cell know what to

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do how do things happen inside the cell

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and outside of the cell well this

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information is transcribed in a process

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called transcription very simple to

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understand so you want to transcribe

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because you want to maintain the

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integrity of the main informational book

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the DNA but you also want promiscuity in

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the message you want the message to be

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able to do things and these messages

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that are transcribed are known as RNA

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RNA sequences or RNA strings and they

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are comprised of our three familiar

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adenine cytosine guanine but also now

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introducing carousel now you have T RNA

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mRNA which stirs messenger RNA and RNA

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ribosomal RNA and those are the three

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main gene products of RNA but you also

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have other forms of RNA such as small

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interfering RNA and a small subunit RNA

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but I'm not going to talk about any of

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those they do other things now when

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you're talking about coding you're

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mainly talking about messenger RNA and

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these are genes so these are messages in

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a string that get translated into the

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catalytic catalytic structural and

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informational products inside the cell

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and these are known as proteins I'm sure

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you've all heard this word before

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proteins do all of the work in

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most of all of the work inside of the

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cell they allow they form you know

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porins or channels in the membrane that

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allow molecules to flow inside and

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outside of the cell they allow for

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structural integrity of the cell so the

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soul just doesn't collapse on itself

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especially in the case of eukaryotic

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cells and they do the transformations of

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molecules inside that cell so catalysis

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and metabolisms you know breaking down

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sugar and forming complicated sugars and

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these proteins are comprised of amino

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acids surprise we're going to talk only

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about amino acids no I'm not going to go

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through all of these because it would

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take too long and nobody wants to say

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here through that but it's important to

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know that the basis code for these amino

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acids when you're talking about proteins

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but how does this translation happen who

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is the monk sitting there going from

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ancient Latin into Old English well that

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is the job of the ribosome it is the

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major hinge of information inside the

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cell so the ribosome is composed of that

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ribosomal RNA so the ribosome is

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actually a complex super structure that

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has some small subunits of proximal RNA

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and some large subunits of ribosomal RNA

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I'm sure you've heard the terms 16s

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maybe before or 30s um that's confusing

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and I'm not going to describe them in

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that way I'm just going to say there's a

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small subunit there's a large subunit

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and they come together and for some of

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us microbiologists out there we also not

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only care about the structural and

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catalytic part of the ribosome but also

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the taxonomic information that it codes

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because if you ever look in taxonomy

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oftentimes species are defined by their

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16s which is one of my favorite

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structures so I have that pictured here

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and induce equalise 16s gene and it's a

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pretty rare

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of secondary structure loops and so you

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can see just like DNA RNA forms these

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secondary structures and it's easy to

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imagine how these loops and turns can

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all fold in on themselves and for

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tertiary structures and then when those

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subunits come together they like any a

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list star get adorned into the fake

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complex with accessory proteins and

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that's what all those chain bows are on

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top of the sprawled core of the ribosome

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so you have your small subunit a large

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subunit and then these accessory

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proteins and no I'm not going to go into

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all the accessory proteins because yet

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again it would take too much time and

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honestly I don't do that research but

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isn't it pretty so this is this so what

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I just went through very briefly and

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very hopefully very simple simply very

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simply and not use too much jargon is

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the central dogma of molecular biology

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is the central dogma of informational

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flow inside the cell you have your main

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core of information your DNA this is the

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book of life and then this gets

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transcribed into short messages that go

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out and get translated and do things so

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it is an oversimplification of how

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information flows inside the cell it if

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I no means correct but it's the easiest

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way to convey it to all of those

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learning this for the first time or

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maybe for the second time but you

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haven't taken a biology class since high

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school okay so that's fascinating but

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you know how did all this begin so as

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you're going to hear today from some of

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the talks or seeing some of the posters

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amongst all of you or the group is

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riddled with prebiotic or origins of

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life investigators and what they're

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looking at is just what the name

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prebiotic implies before a large

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functional cell comes together what

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happened how did that how did this

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information become more and more complex

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well the predominant hypothesis or

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thought is that

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the world origins of life actually

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started as an RNA world so you have an

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RNA string that started and became more

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and more complicated with time now this

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would be an imply like a ribosomal world

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so you're not just talking about a

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string of information you need that

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information to actually be functional to

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and ribozymes as I said our catalytic as

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well as informational so they're

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obviously the dream of all origins of

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life researchers um obviously I'm not

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one so I'm talking in broad general

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terms for all of you but what they're

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looking at is they're looking at the

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evolution of the ribozyme so how did it

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has it changed through the three billion

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years of life on this planet and also

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how is it different or how is it

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actually very similar amongst all the

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branches of life so that's more of the

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evolutionary in the taxonomy and the

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phylogenetic they're also looking at

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some of the look at non-canonical basis

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which if some of you know bradley

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rapport that is what his research was as

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a PhD student so you're looking at

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obviously we have the four bases now for

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RNA but was that always the case

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probably not and there's actually a

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multitude of base units that can be used

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or incorporated into RNA and so that

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would be a non-canonical based research

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and then there's others that also look

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at all of those blinged-out bedazzled

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accessory proteins on the interior kind

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of middle area and exterior of the

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ribosome and so that's looking at how

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these proteins actually modulate and

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influence the in general overall

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functionality of throw its own so now

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that I am done with my very simple and

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very quick talk I talk a lot faster when

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I'm nervous even if I'm looking at my

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own screen and not any of you um but now

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it's time for the real research so I

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hope that some of the concepts that I

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briefly went over will allow you to

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understand they're very awesome research

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because I

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I think that we have a pretty good

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conference this year and entities so

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with that thank all of you will have

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anything else unless somebody must ask

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some questions and I'll attempt to to

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answer them and Brett will be taking

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over as chair for this session since I

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am out there and I can't regulate stuff