Methanospirillum stamsii sp. nov., a psychrotolerant, hydrogenotrophic, methanogenic archaeon isolated from an anaerobic expanded granular sludge bed bioreactor operated at low temperature.
A psychrotolerant hydrogenotrophic methanogen, strain Pt1, was isolated from a syntrophic propionate-oxidizing methanogenic consortium obtained from granulated biomass of a two-stage low-temperature (3-8 °C) anaerobic expanded granular sludge bed (EGSB) bioreactor, fed with a mixture of volatile fatty acids (VFAs) (acetate, propionate and butyrate). The strain was strictly anaerobic, and cells were curved rods, 0.4-0.5×7.5-25 µm, that sometimes formed wavy filaments from 25 to several hundred micrometres in length. Cells stained Gram-negative and were non-sporulating. They were gently motile by means of tufted flagella. The strain grew at 5-37 °C (optimum at 20-30 °C), at pH 6.0-10 (optimum 7.0-7.5) and with 0-0.3 M NaCl (optimum 0 M NaCl). Growth and methane production was found with H2/CO2 and very weak growth with formate. Acetate and yeast extract stimulated growth, but were not essential. The G+C content of the DNA of strain Pt1 was 40 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Pt1 was a member of the genus Methanospirillum and showed 97.5 % sequence similarity to Methanospirillum hungatei JF1(T) and 94 % sequence similarity to Methanospirillum lacunae Ki8-1(T). DNA-DNA hybridization of strain Pt1 with Methanospirillum hungatei JF1(T) revealed 39 % relatedness. On the basis of its phenotypic characteristics and phylogenetic position, strain Pt1 is a representative of a novel species of the genus Methanospirillum, for which the name Methanospirillum stamsii sp. nov. is proposed. The type strain is Pt1(T) ( = DSM 26304(T) = VKM B-2808(T)).
Winogradsky Institute of Microbiology Russian Academy of Sciences, Moscow, Russia.
Sofiya N
SN
Parshina
Winogradsky Institute of Microbiology Russian Academy of Sciences, Moscow, Russia.
Anna V
AV
Ermakova
VTT Technical Research Centre of Finland, Espoo, Finland.
Malin
M
Bomberg
Winogradsky Institute of Microbiology Russian Academy of Sciences, Moscow, Russia.
Ekaterina N
EN
Detkova
D001482:Base Composition; D019149:Bioreactors / Q000382:microbiology*; D003080:Cold Temperature; D019641:DNA, Archaeal / Q000235:genetics; D019639:Methanospirillum / Q000145:classification* / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009426:Netherlands; D009693:Nucleic Acid Hybridization; D010088:Oxidoreductases / Q000235:genetics; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*; D013696:Temperature
D019641:DNA, Archaeal; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D010088:Oxidoreductases; C021572:methyl coenzyme M reductase