title: Methanospirillum psychrodurum sp. nov., isolated from wetland soil.
abstract: A psychrotolerant methanogenic strain, X-18(T), was isolated from the soil of the Madoi wetland at Qinghai, Tibetan plateau, China. Cells were wavy rods (11-62 µm long) with blunt tapered ends and Gram-stain-negative. Strain X-18(T) grew strictly anaerobically and produced methane exclusively from H2/CO2. Growth occurred in the temperature range of 4-32 °C and optimally at 25 °C. Growth pH ranged from 6.5 to 8.0 and the optimum was 7.0. The G+C content of the genomic DNA of strain X-18(T) was 44.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences and the alpha subunit of methyl-coenzyme M reductase indicated that strain X-18(T) was affiliated to the genus Methanospirillum and was most closely related to Methanospirillum lacunae Ki8-1(T), with 96.3% 16S rRNA gene sequence similarity. However, strain X-18(T) could be distinguished from the existing species of the genus Methanospirillum by its lower growth temperature and obligate hydrogenotrophic methanogenesis. On the basis of phenotypic characteristics and phylogenetic analysis, strain X-18(T) represents a novel species of the genus Methanospirillum, for which the name Methanospirillum psychrodurum sp. nov. is proposed and strain X-18(T) is assigned as the type strain ( = CGMCC 1.5186(T) = JCM 19216(T)).
authors.affiliation: University of Chinese Academy of Sciences, Beijing 100049, PR China.|State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China.
authors.forename: Liguang
authors.initials: L
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China.
authors.forename: Xiuzhu
authors.initials: X
authors.lastname: Dong
mesh_terms: D001482:Base Composition; D002681:China; D019641:DNA, Archaeal / Q000235:genetics; D008697:Methane / Q000096:biosynthesis; D019639:Methanospirillum / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000235:genetics; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D053833:Wetlands
chemical_list: D019641:DNA, Archaeal; D012336:RNA, Ribosomal, 16S; D010088:Oxidoreductases; C021572:methyl coenzyme M reductase; D008697:Methane