Thalassorhabdus aurantiaca gen. nov., sp. nov., a new member of the family Flavobacteriaceae isolated from seawater in South Korea

Abstract

A novel Gram-negative, orange pigmented, strictly aerobic bacterium, designated strain IP9, was isolated from seawater at the sea shore of Incheon Eulwang-ri beach, South Korea. Cells of strain IP9 were observed to be straight or slightly curved rods and colonies to be round and convex. Strain IP9 was found to be catalase and oxidase positive, and non-motile. Growth was observed in the temperature range of 10-37 °C (optimum at 30 °C), pH range of 6-10 (optimum at pH 7-8) and salt concentration range of 0-7% (w/v) NaCl (optimum at 0-1%). On the basis of 16S rRNA gene sequence similarity and phylogenetic analysis, strain IP9 was found to be related to the members of the family Flavobacteriaceae, being closely related to Hwangdonia seohaensis KCTC 32177 (95.3% sequence similarity). The DNA G + C content of the novel strain was determined to be 39.1 mol%. The major polar lipids were found to be phosphatidylethanolamine, three unidentified aminoglycolipids and two unidentified glycolipids. The major fatty acids (> 10%) were identified as iso-C and iso-C 3-OH. The predominant quinone was found to be menaquinone 6 (MK-6). Based on the biochemical, phylogenetic and physiological data, we conclude that strain IP9 (= KCTC 52523 = JCM 31732) represents the type species of a novel genus of the family Flavobacteriaceae for which the name Thalassorhabdus aurantiaca gen. nov., sp. nov. is proposed.