Methylopila jiangsuensis sp. nov., an aerobic, facultatively methylotrophic bacterium

The taxonomic status was determined of an aerobic, facultatively methylotrophic strain, JZL-4T, isolated from activated sludge. The cells were Gram-negative, asporogenous, colourless, motile, short rods. The strain utilized methanol, methylamine, formate and a variety of polycarbon compounds, but not methane, dichloromethane or CO2/H2, as carbon and energy sources. C1 compounds were assimilated via the isocitrate lyase-negative serine pathway. Optimal growth occurred at 30 °C, pH 6.5–7.5 and 0.5 % (w/v) NaCl. The major cellular fatty acids were C18 : 1ω7c and C18 : 0. The major phospholipids were phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol and phosphatidylmonomethylethanolamine (PME); PME, the main phospholipid of strain JZL-4T, was absent or present in only minor amounts in Methylopila capsulata IM1T, Methylopila helvetica DM9T and Albibacter methylovorans DM10T. The major ubiquinone was Q-10. The DNA G+C content of strain JZL-4T was 70.4 mol% (T m). Phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain showed high sequence similarities to M. capsulata IM1T (97.2 %), A. methylovorans DM10T (94.9 %) and M. helvetica DM9T (94.1 %), and showed less than 94 % similarity to strains of other species with validly published names. Strain JZL-4T had a low level of DNA–DNA relatedness (34 %) with M. capsulata IM1T. On the basis of phenotypic, genetic and phylogenetic data, strain JZL-4T is proposed to represent a novel species of the genus Methylopila, with the name Methylopila jiangsuensis sp. nov. The type strain is strain JZL-4T ( = ACCC 05406T  = DSM 22718T  = VKM B-2555T).