Jannaschia confluentis sp. nov., isolated from the junction between the ocean and a freshwater spring

A Gram-stain-negative, aerobic, non-motile and ovoid or rod-shaped bacterial strain, designated JSSK-16^T, was isolated from the place where the ocean and a freshwater spring meet at Jeju Island, South Korea. Strain JSSK-16^T grew optimally at 30 °C, at pH 6.5-8.0 and in the presence of 2.0-4.0 % (w/v) NaCl. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain JSSK-16^T joined the clade comprising the type strains of Jannaschia species. Strain JSSK-16^T exhibited 16S rRNA gene sequence similarity values of 97.5 and 97.1 % to the type strains of Jannaschia donghaensis and Jannaschia faecimaris, respectively, and of 94.1-96.6 % to the type strains of the other Jannaschia species. Strain JSSK-16^T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c, 11-methyl C18 : 1ω7c and C18 : 0 as the major fatty acids. The major polar lipids detected in strain JSSK-16^T were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content of strain JSSK-16T was 68.8 mol% and its DNA-DNA relatedness values with the type strains of J. donghaensis and J. faecimaris were 18 and 12, respectively. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain JSSK-16^T is separated from recognized species of the genus Jannaschia. On the basis of the data presented, strain JSSK-16^T is considered to represent a novel species of the genus Jannaschia, for which the name Jannaschia confluentis sp. nov. is proposed. The type strain is JSSK-16T (=KACC 19436^T=KCTC 62137^T=NBRC 113018^T).