Microbulbifer okhotskensis sp. nov., isolated from a deep bottom sediment of the Okhotsk Sea.

A Gram-negative, aerobic, non-motile bacterium КMM 9862 was isolated from a deep bottom sediment sample obtained from the Okhotsk Sea, Russia. Based on the 16S rRNA gene and whole genome sequences analyses the novel strain КMM 9862 fell into the genus Microbulbifer (class Gammaproteobacteria) sharing the highest 16S rRNA gene sequence similarities of 97.4% to Microbulbifer echini AM134 and Microbulbifer epialgicus F-104, 97.3% to Microbulbifer pacificus SPO729, 97.1% to Microbulbifer variabilis ATCC 700307, and similarity values of < 97.1% to other recognized Microbulbifer species. The average nucleotide identity and digital DNA-DNA hybridization values between strain КMM 9862 and M. variabilis ATCC 700307 and M. thermotolerans DSM 19189 were 80.34 and 77.72%, and 20.2 and 19.0%, respectively. Strain КMM 9862 contained Q-8 as the predominant ubiquinone and C, C ω7c, C, and C 3-OH as the major fatty acids. The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, an unidentified aminophospholipid, an unidentified aminolipid, two unidentified phospholipids, phosphatidic acid, and an unidentified lipid. The DNA G+C content of 49.8% was calculated from the genome sequence. On the basis of the phylogenetic evidence and distinctive phenotypic characteristics, the marine bacterium KMM 9862 is proposed to be classified as a novel species Microbulbifer okhotskensis sp. nov. The type strain of the species is strain KMM 9862 (= KACC 22804).