Abstract

Hydrogen produced during water-rock serpentinization reactions can drive the synthesis of organic compounds both biotically and abiotically. We investigated abiotic carbon production and microbial metabolic pathways at the high energy but low diversity serpentinite-hosted Lost City hydrothermal field. Compound-specific 14C data demonstrates that formate is mantle-derived and abiotic in some locations and has an additional, seawater-derived component in others. Lipids produced by the dominant member of the archaeal community, the Lost City Methanosarcinales, largely lack 14C, but metagenomic evidence suggests they cannot use formate for methanogenesis. Instead, sulfate-reducing bacteria may be the primary consumers of formate in Lost City chimneys. Paradoxically, the archaeal phylotype that numerically dominates the chimney microbial communities appears ill suited to live in pure hydrothermal fluids without the co-occurrence of organisms that can liberate CO2. Considering the lack of dissolved inorganic carbon in such systems, the ability to utilize formate may be a key trait for survival in pristine serpentinite-hosted environments.

Details

Title
Deeply-sourced formate fuels sulfate reducers but not methanogens at Lost City hydrothermal field
Author
Lang, Susan Q 1 ; Früh-Green, Gretchen L 2 ; Bernasconi, Stefano M 2   VIAFID ORCID Logo  ; Brazelton, William J 3 ; Schrenk, Matthew O 4 ; McGonigle, Julia M 3 

 School of Earth, Ocean, and Environment, University of South Carolina, Columbia, SC, USA; Department of Earth Sciences, ETH Zürich, Zurich, Switzerland 
 Department of Earth Sciences, ETH Zürich, Zurich, Switzerland 
 Department of Biology, University of Utah, Salt Lake City, UT, USA 
 Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI, USA 
Pages
1-10
Publication year
2018
Publication date
Jan 2018
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
1987709799
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.