Autotrophy as a predominant mode of carbon fixation in anaerobic methane-oxidizing microbial communities

The methane-rich, hydrothermally heated sediments of the Guaymas Basin are inhabited by thermophilic microorganisms, including anaerobic methane-oxidizing archaea (mainly ANME-1) and sulfate-reducing bacteria (e.g., HotSeep-1 cluster). We studied the microbial carbon flow in ANME-1/ HotSeep-1 enrich...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2012-11, Vol.109 (47), p.19321-19326
Main Authors: Kellermann, Matthias Y, Wegener, Gunter, Elvert, Marcus, Yoshinaga, Marcos Yukio, Lin, Yu-Shih, Holler, Thomas, Mollar, Xavier Prieto, Knittel, Katrin, Hinrichs, Kai-Uwe
Format: Article
Language:English
Subjects:
Anaerobiosis
Archaea
Autotrophic Processes - physiology
autotrophs
Bacteria
Bacteria - metabolism
bacterial communities
basins
Biological Sciences
biosynthesis
Biota
Carbon
Carbon - metabolism
Carbon Cycle - physiology
Carbon Isotopes
Isotope Labeling
Isotopes
Lipid Metabolism
Lipids
Marine sediments
Methane
Methane - metabolism
Mexico
Microbiology
Microorganisms
Molecular Sequence Data
Oxidation
Oxidation-Reduction
Sea water
Sediments
stable isotopes
sulfate-reducing bacteria
thermophilic microorganisms
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The methane-rich, hydrothermally heated sediments of the Guaymas Basin are inhabited by thermophilic microorganisms, including anaerobic methane-oxidizing archaea (mainly ANME-1) and sulfate-reducing bacteria (e.g., HotSeep-1 cluster). We studied the microbial carbon flow in ANME-1/ HotSeep-1 enrichments in stable-isotope–probing experiments with and without methane. The relative incorporation of ¹³C from either dissolved inorganic carbon or methane into lipids revealed that methane-oxidizing archaea assimilated primarily inorganic carbon. This assimilation is strongly accelerated in the presence of methane. Experiments with simultaneous amendments of both ¹³C-labeled dissolved inorganic carbon and deuterated water provided further insights into production rates of individual lipids derived from members of the methane-oxidizing community as well as their carbon sources used for lipid biosynthesis. In the presence of methane, all prominent lipids carried a dual isotopic signal indicative of their origin from primarily autotrophic microbes. In the absence of methane, archaeal lipid production ceased and bacterial lipid production dropped by 90%; the lipids produced by the residual fraction of the metabolically active bacterial community predominantly carried a heterotrophic signal. Collectively our results strongly suggest that the studied ANME-1 archaea oxidize methane but assimilate inorganic carbon and should thus be classified as methane-oxidizing chemoorganoautotrophs.
ISSN:0027-8424
1091-6490
DOI:10.1073/pnas.1208795109