Agarivorans litoreus sp. nov., a novel gammaproteobacterium isolated from seawater and emended description of the genus Agarivorans.

A Gram-stain negative, aerobic, non-spore-forming, motile and rod-shaped or ovoid bacterial strain, designated GJSW-6(T), was isolated from a seawater collected at Geoje island on the South Sea, South Korea, and subjected to polyphasic taxonomic study. Strain GJSW-6(T) was found to grow optimally at 30 °C, at pH 7.0-8.0 and in the presence of approximately 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain GJSW-6(T) clustered with the type strains of two Agarivorans species, Agarivorans albus and Agarivorans gilvus, with which it exhibited sequence similarity values of 99.17 and 95.88 %, respectively. Sequence similarities to the type strains of the other recognized species were less than 93.04 %. Strain GJSW-6(T) was found to contain Q-8 as the predominant ubiquinone and C16:0, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) and C18:1 ω7c as the major fatty acids. The polar lipid profile of strain GJSW-6(T) containing phosphatidylethanolamine and phosphatidylglycerol as major components was similar to those of the type strains of A. albus and A. gilvus. The DNA G+C content of strain GJSW-6(T) was determined to be 45.3 mol% and its mean DNA-DNA relatedness value with A. albus JCM 21469(T) was 19 %. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain GJSW-6(T) is separated from two Agarivorans species. On the basis of the data presented, strain GJSW-6(T) is considered to represent a novel species of the genus Agarivorans, for which the name Agarivorans litoreus sp. nov. is proposed. The type strain is GJSW-6(T) (= KCTC 42116(T) = NBRC 110444(T)). An emended description of the genus Agarivorans is also proposed.