title: Methanococcoides vulcani sp. nov., a marine methylotrophic methanogen that uses betaine, choline and N,N-dimethylethanolamine for methanogenesis, isolated from a mud volcano, and emended description of the genus Methanococcoides.
abstract: A novel, strictly anaerobic, methylotrophic marine methanogen, strain SLH33(T), was isolated from deep sediment samples covered by an orange microbial mat collected from the Napoli Mud Volcano. Cells of strain SLH33(T) were Gram-stain-negative, motile, irregular cocci that occurred singly. Cells utilized trimethylamine, dimethylamine, monomethylamine, methanol, betaine, N,N-dimethylethanolamine and choline (N,N,N-trimethylethanolamine) as substrates for growth and methanogenesis. The optimal growth temperature was 30 °C; maximum growth rate was obtained at pH 7.0 in the presence of 0.5 M Na(+). The DNA G+C content of strain SLH33(T) was 43.4 mol%. Phylogenetic analyses based on 16S rRNA gene sequences placed strain SLH33(T) within the genus Methanococcoides. The novel isolate was related most closely to Methanococcoides methylutens TMA-10(T) (98.8% 16S rRNA gene sequence similarity) but distantly related to Methanococcoides burtonii DSM 6242(T) (97.6%) and Methanococcoides alaskense AK-5(T) (97.6%). DNA-DNA hybridization studies indicated that strain SLH33(T) represents a novel species, given that it shared less than 16% DNA-DNA relatedness with Methanococcoides methylutens TMA-10(T). The name Methanococcoides vulcani sp. nov. is proposed for this novel species, with strain SLH33(T) ( = DSM 26966(T) = JCM 19278(T)) as the type strain. An emended description of the genus Methanococcoides is also proposed.
authors.affiliation: Ifremer, UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Technopôle Pointe du diable, F-29280 Plouzané, France.|CNRS, IUEM - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.|Université de Bretagne Occidentale (UBO, UEB), Institut Universitaire Européen de la Mer (IUEM) - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: L'Haridon
authors.affiliation: Ifremer, UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Technopôle Pointe du diable, F-29280 Plouzané, France.|CNRS, IUEM - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.|Université de Bretagne Occidentale (UBO, UEB), Institut Universitaire Européen de la Mer (IUEM) - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.
authors.forename: Morgane
authors.initials: M
authors.lastname: Chalopin
authors.affiliation: Ifremer, UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Technopôle Pointe du diable, F-29280 Plouzané, France.|CNRS, IUEM - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.|Université de Bretagne Occidentale (UBO, UEB), Institut Universitaire Européen de la Mer (IUEM) - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Colombo
authors.affiliation: Ifremer, UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Technopôle Pointe du diable, F-29280 Plouzané, France.|CNRS, IUEM - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.|Université de Bretagne Occidentale (UBO, UEB), Institut Universitaire Européen de la Mer (IUEM) - UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes (LMEE), Place Nicolas Copernic, F-29280 Plouzané, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Toffin
mesh_terms: D001482:Base Composition; D001622:Betaine / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D003642:Deanol / Q000378:metabolism; D060086:Hydrothermal Vents / Q000382:microbiology*; D008522:Mediterranean Sea; D017019:Methanosarcinaceae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010802:Phylogeny; D010858:Pigmentation; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D003642:Deanol; D001622:Betaine; D002794:Choline