title: Diversity of functional genes of methanogens, methanotrophs and sulfate reducers in deep-sea hydrothermal environments.
abstract: To contribute to the identification of methanogens, methanotrophs and sulfate-reducing bacteria (SRB) in microbial communities from the 13 degrees N (East Pacific Rise) and Rainbow (Mid-Atlantic Ridge) hydrothermal vent fields, we investigated the diversity of mcrA, pmoA and dsrAB genes sequences. Clone libraries were obtained using DNA isolated from fragments of diffuse vents, sediment and in situ samplers. The clones were categorized by restriction fragment length polymorphism, and representatives of each group were sequenced. Sequences were related to that of hyperthermophilic (order Methanopyrales and family Methanocaldococcaceae), thermophilic and mesophilic (family Methanococcaceae) methanogens, thermophilic (proposed genus 'Methylothermus') and mesophilic type I methanotrophs, and hyperthermophilic (order Archaeoglobales), thermophilic (order Thermodesulfobacteriales) and mesophilic (family Desulfobulbaceae) SRB. Several of the obtained sequences were distantly related to the genes of cultivated organisms, providing evidence of the existence of novel lineages in the three functional groups. This study provides for the first time an insight into the diversity of several functional genes of deep-sea hydrothermal system microorganisms.
authors.affiliation: UMR 6539, Laboratoire des Sciences de l'Environnement Marin, Centre National de la Recherche Scientifique, Institut Universitaire Européen de la Mer, Technopôle Brest-Iroise, Place Nicolas Copernic, 29280 Plouzané, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Nercessian
authors.forename: Nadège
authors.initials: N
authors.lastname: Bienvenu
authors.forename: David
authors.initials: D
authors.lastname: Moreira
authors.forename: Daniel
authors.initials: D
authors.lastname: Prieur
authors.forename: Christian
authors.initials: C
authors.lastname: Jeanthon
mesh_terms: D019843:Archaeal Proteins / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D020564:Deltaproteobacteria / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D019605:Euryarchaeota / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D014644:Genetic Variation; D008697:Methane / Q000378:metabolism; D000432:Methanol / Q000378:metabolism; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000235:genetics* / Q000378:metabolism; D010105:Oxygenases / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012623:Seawater / Q000382:microbiology; D017422:Sequence Analysis, DNA; D013431:Sulfates / Q000378:metabolism
chemical_list: D019843:Archaeal Proteins; D001426:Bacterial Proteins; D013431:Sulfates; D010088:Oxidoreductases; D010105:Oxygenases; C021555:methane monooxygenase; D050862:Oxidoreductases Acting on Sulfur Group Donors; C021572:methyl coenzyme M reductase; D008697:Methane; D000432:Methanol