Archaeal and anaerobic methane oxidizer communities in the Sonora Margin cold seeps, Guaymas Basin (Gulf of California).
ISME J. 2013 Aug; 7(8):1595-608.IJ

Abstract

Cold seeps, located along the Sonora Margin transform fault in the Guaymas Basin, were extensively explored during the 'BIG' cruise in June 2010. They present a seafloor mosaic pattern consisting of different faunal assemblages and microbial mats. To investigate this mostly unknown cold and hydrocarbon-rich environment, geochemical and microbiological surveys of the sediments underlying two microbial mats and a surrounding macrofaunal habitat were analyzed in detail. The geochemical measurements suggest biogenic methane production and local advective sulfate-rich fluxes in the sediments. The distributions of archaeal communities, particularly those involved in the methane cycle, were investigated at different depths (surface to 18 cm below the sea floor (cmbsf)) using complementary molecular approaches, such as Automated method of Ribosomal Intergenic Spacer Analysis (ARISA), 16S rRNA libraries, fluorescence in situ hybridization and quantitative polymerase chain reaction with new specific primer sets targeting methanogenic and anaerobic methanotrophic lineages. Molecular results indicate that metabolically active archaeal communities were dominated by known clades of anaerobic methane oxidizers (archaeal anaerobic methanotroph (ANME)-1, -2 and -3), including a novel 'ANME-2c Sonora' lineage. ANME-2c were found to be dominant, metabolically active and physically associated with syntrophic Bacteria in sulfate-rich shallow sediment layers. In contrast, ANME-1 were more prevalent in the deepest sediment samples and presented a versatile behavior in terms of syntrophic association, depending on the sulfate concentration. ANME-3 were concentrated in small aggregates without bacterial partners in a restricted sediment horizon below the first centimetres. These niche specificities and syntrophic behaviors, depending on biological surface assemblages and environmental availability of electron donors, acceptors and carbon substrates, suggest that ANME could support alternative metabolic pathways than syntrophic anaerobic oxidation of methane.

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Authors+Show Affiliations

Vigneron A
DEEP/LM2E, IFREMER, Laboratoire de Microbiologie des Environnements Extrêmes, UMR6197, Technopôle Brest Iroise, Plouzané, France.
Cruaud P
No affiliation info available
Pignet P
No affiliation info available
Caprais JC
No affiliation info available
Cambon-Bonavita MA
No affiliation info available
Godfroy A
No affiliation info available
Toffin L
No affiliation info available

MeSH

ArchaeaBacteriaBacterial Physiological PhenomenaBiodiversityCaliforniaGeologic SedimentsIn Situ Hybridization, FluorescenceMethaneOceans and SeasOxidation-ReductionPhylogenyRNA, Ribosomal, 16SSeawaterSulfates

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

23446836