Methyloradius palustris gen. nov., sp. nov., a methanol-oxidizing bacterium isolated from snow.

A novel methylotrophic bacterium, strain Zm11, was isolated from reddish brown snow collected in a moor in Japan. Cells of the isolate were Gram-stain-negative, motile, and rod-shaped (0.6-0.7 × 1.2-2.7 μm). Growth was observed at 5-32 °C with an optimum growth temperature of 25-28 °C. The pH range for growth was 5.4-7.8 with an optimum pH of 6.8. The strain utilized only methanol as carbon and energy sources for aerobic growth. The major cellular fatty acids (> 40% of total) were summed feature 3 (Cω7c and/or Cω6c) and C. The predominant quinone was Q-8, and major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The complete genome of strain Zm11 is composed of a circular chromosome (2,800,413 bp), with G + C content of 46.4 mol%. Phylogenetic analyses were conducted based on the 16S rRNA gene sequence and conserved proteins encoded in the genome. The results of analyses indicate that strain Zm11 is a member of the family Methylophilaceae but does not belong to any existing genus. On the basis of its genomic and phenotypic properties, strain Zm11 (= DSM111909 = NBRC114766) is proposed as the type strain of a new species in a new genus, Methyloradius palustris gen. nov., sp. nov.