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, Agarivoransalbus and Agarivoransgilvus, 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 C_16:0, summed feature 3 (C_16:1ω7c and/or C_16:1ω6c) and C_18:1ω7c 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.