Octadecabacter ponticola sp. nov., isolated from seawater

A Gram-stain-negative, non-spore-forming, non-flagellated and coccoid, ovoid or rod-shaped bacterial strain, HDSW-34^T, was isolated from seawater of Hwang-do on the Yellow Sea, South Korea, and subjected to a taxonomic study using a polyphasic approach. Strain HDSW-34^T grew optimally at 30 °C, at pH 7.0–8.0 and in the presence of 1.0–2.0% (w/v) NaCl. Neighbourjoining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain HDSW-34^Tclustered with the type strains of four species of the genus Octadecabacter, showing 96.7–97.6% sequence similarity. Strain HDSW-34^T contained Q-10 as the predominant ubiquinone and C_{18: 1}ω7c as the major fatty acid. The major polar lipids detected in strain HDSW-34^T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain HDSW-34^T was 62.0 mol% and its DNA–DNA relatedness values with Octadecabacter antarcticus CIP 106731^T and Octadecabacter arcticus DSM 13978^T were 11–18 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain HDSW-34^T is separated from other recognized species of the genus Octadecabacter. On the basis of the data presented, strain HDSW-34^T is considered to represent a novel species of the genus Octadecabacter, for which the name Octadecabacter ponticola sp. nov. is proposed. The type strain is HDSW-34^T (= KCTC 52250^T=NBRC 112296^T).