A Gram-stain-negative, yellow-pigmented, aerobic bacterial strain, designated LPB0140T, was isolated from sea water. The 16S rRNA gene sequence similarity analysis demonstrated that the closest relative of the isolate is Sphingorhabdus contaminans (96.4 %), but the new isolate formed an independent phyletic line within the genus Sphingorhabdus. Its genome is composed of a circular chromosome of 2.53 Mb with DNA G+C content of 46.1 mol%. The genome includes 2359 protein-coding genes, and two copies of rRNA operons. Strain LPB0140T possessed C14 : 0 2-OH, C16 : 1ω7c and/or C16 : 1ω6c, and C18 : 1ω7c and/or C18 : 1ω6c as the major cellular fatty acids and Q-10 as the isoprenoid quinone. The major polar lipids were phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, and sphingoglycolipid, but phosphatidylmonomethylethanolamine and phosphatidyldimethylethanolamine were also detected as minor polar lipids. The chemotaxonomic properties and enzymatic activities of the novel isolate clearly differed from those of its closest relatives. Thus, based on the phylogenetic and phenotypic data presented in this study, strain LPB0140T should be classified as a novel species in the genus Sphingorhabdus. The type strain is LPB0140T (=KACC18891T=JCM31568T).
Keywords: Sphingorhabdus; Sphingorhabdus lutea; sphingolipid.