title: Membrane lipid patterns typify distinct anaerobic methanotrophic consortia.
abstract: The anaerobic oxidation of methane (AOM) is one of the major sinks of this substantial greenhouse gas in marine environments. Recent investigations have shown that diverse communities of anaerobic archaea and sulfate-reducing bacteria are involved in AOM. Most of the relevant archaea are assigned to two distinct phylogenetic clusters, ANME-1 and ANME-2. A suite of specific (13)C-depleted lipids demonstrating the presence of consortia mediating AOM in fossil and recent environments has been established. Here we report on substantial differences in the lipid composition of microbial consortia sampled from distinct compartments of AOM-driven carbonate reefs growing in the northwestern Black Sea. Communities in which the dominant archaea are from the ANME-1 cluster yield internally cyclized tetraether lipids typical of thermophiles. Those in which ANME-2 archaea are dominant yield sn-2-hydroxyarchaeol accompanied by crocetane and crocetenes. The bacterial lipids from these communities are also distinct even though the sulfate-reducing bacteria all belong to the Desulfosarcina/Desulfococcus group. Nonisoprenoidal glycerol diethers are predominantly associated with ANME-1-dominated communities. Communities with ANME-2 yield mainly conventional, ester-linked diglycerides. ANME-1 archaea and associated sulfate-reducing bacteria seem to be enabled to use low concentrations of methane and to grow within a broad range of temperatures. Our results offer a tool for the study of recent and especially of fossil methane environments.
authors.affiliation: Institute of Biogeochemistry and Marine Chemistry, University of Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Blumenberg
authors.forename: Richard
authors.initials: R
authors.lastname: Seifert
authors.forename: Joachim
authors.initials: J
authors.lastname: Reitner
authors.forename: Thomas
authors.initials: T
authors.lastname: Pape
authors.forename: Walter
authors.initials: W
authors.lastname: Michaelis
mesh_terms: D001421:Bacteria, Anaerobic / Q000145:classification* / Q000254:growth & development; D005843:Geography; D008563:Membrane Lipids / Q000032:analysis*; D017014:Methanobacterium / Q000145:classification* / Q000254:growth & development; D010802:Phylogeny; D014871:Water Microbiology
chemical_list: D008563:Membrane Lipids