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bioRxiv · 10.1101/272039

Specific enrichment of hyperthermophilic electroactive Archaea from deep-sea hydrothermal vent on electrically conductive support

Guillaume, P.·Frouin, E.·Pasero, E.·Godfroy, A.·Combet-Blanc, Y.·Davidson, S.·Liebgott, P.-P.
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Abstract

While more and more investigations are done to isolate hyperthermophilic exoelectrogenic communities from environments, none have been performed yet on deep-sea hydrothermal vent. Samples of black smoker chimney from Rainbow site on the Atlantic mid-oceanic ridge have been harvested for enriching exoelectrogens in microbial electrolysis cells under hyperthermophilic (80{degrees}C) condition. Two enrichments have been performed: one from direct inoculation of crushed chimney and the other one from inoculation of a pre-cultivation on iron (III) oxide. In both experiments, a current production was observed from 2.4 A/m2 to 5.8 A/m2 with a set anode potential of +0.05 vs SHE. Taxonomic affiliation of the exoelectrogen communities obtained exhibited a specific enrichment of Archaea from Thermococcales and Archeoglobales orders on the electrode, even when both inocula were dominated by Bacteria.

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Guillaume, P., Frouin, E., Pasero, E., Godfroy, A., Combet-Blanc, Y., Davidson, S., Liebgott, P.-P.. 2018-02-26. Specific enrichment of hyperthermophilic electroactive Archaea from deep-sea hydrothermal vent on electrically conductive support. https://doi.org/10.1101/272039

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