Pontivivens insulae gen. nov., sp. nov., isolated from seawater

A Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated GYSW-23(T), was isolated from seawater off Geoje island in the South Sea, South Korea. Strain GYSW-23(T) grew optimally at 25 °C, at pH 7.0-8.0 and in the presence of approximately 2.0-3.0% (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain GYSW-23(T) forms a distinct evolutionary lineage independent of other taxa of the family Rhodobacteraceae. It exhibited 16S rRNA gene sequence similarity values of 94.0, 93.5, 93.4 and 93.4% to the type strains of Roseovarius aestuarii, Ruegeria marina, Roseovarius pacificus and Oceanicola litoreus, respectively, and 93.6% to 'Actibacterium atlanticum' 22II-S11-z10. Strain GYSW-23(T) contained Q-10 as the predominant ubiquinone and C18  :  1ω7c as the major fatty acid. The major polar lipids of strain GYSW-23(T) were phosphatidylcholine, phosphatidylglycerol and one unidentified aminolipid. The fatty acid and polar lipid profiles of strain GYSW-23(T) were distinguishable from those of the phylogenetically related taxa. The DNA G+C content of strain GYSW-23(T) was 60.6 mol%. On the basis of the phylogenetic, chemotaxonomic and other phenotypic properties, strain GYSW-23(T) is considered to represent a novel species of a new genus in the family Rhodobacteraceae, for which the name Pontivivens insulae gen. nov., sp. nov. is proposed. The type strain of Pontivivens insulae is GYSW-23(T) ( = KCTC 42458(T) = CECT 8812(T)).