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hi i'm devin payne and i'm going to be

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talking about the reductive dissolution

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of pyrite by methanogens and its

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physiological consequences

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so we've shown that methanogens can

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reduce pyrite by growing these cells

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with either pyrite or chronological

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forms of iron and sulfur

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and we see that when the cells grow with

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pyrite they reduce it and produce

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sulfide that's measurable in solution in

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our biotic cultures

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but not in our abiotic microcosms and

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this research was published in the isme

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journal this year where we also showed

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that methanogens require direct surface

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access to pyrite to grow

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where when cells are provided with

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pyrite that's green solution they grow

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very well

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however when pirates sequester dialysis

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tubing we see no growth and this

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finding was further corroborated by our

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observations of cells growing in close

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contact with the minerals

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this growth on pirate has physiological

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effects at the level of cell size and

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the amount of iron per cell

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where pyrite grown cells are smaller and

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accumulate more iron than ferrous iron

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and sulfide grown cells

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this research was recently accepted in

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the journal bacteriology

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with that i would like to acknowledge my

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mentor dr eric spoyd our boyd lab

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members collaborators and our funding

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sources which includes the department of