Ponticoccus litoralis gen. nov., sp. nov., a marine bacterium in the family Rhodobacteraceae

Abstract

A Gram-negative, coccoid to rod-shaped, strictly aerobic bacterium, strain CL-GR66(T), was isolated from coastal seawater collected off Korea. The strain grew optimally in the presence of 3-5 % sea salts, at a temperature of 30 degrees C and at pH 7. The polar lipid profile of strain CL-GR66(T) comprised phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, two unidentified aminolipids, an unidentified glycolipid and an unidentified lipid. The major fatty acids were C(18 : 1)omega7c (71.4 %), 11-methyl C(18 : 1)omega7c (11.3 %), C(16 : 0) (6.4 %)(,) C(18 : 0) (4.6 %) and C(12 : 1) 3-OH (3.0 %). Ubiquinone 10 was the major quinone. The DNA G+C content was 67.9 mol%. 16S rRNA gene sequence analysis revealed that strain CL-GR66(T) belonged to the Roseobacter clade within the family Rhodobacteraceae. Strain CL-GR66(T) was related most closely to the type strain of Marinovum algicola (95.5 % 16S rRNA gene sequence similarity), and sequence similarities between strain CL-GR66(T) and other type species of the Roseobacter clade ranged from 91.8 to 95.4 %. Phylogenetic analyses of 16S rRNA gene sequences showed that strain CL-GR66(T) was not associated with any known genus in the family Rhodobacteraceae. The distinct phylogenetic position of strain CL-GR66(T), its phylogenetic distance from genera of the family Rhodobacteraceae, together with phenotypic data, suggest that the organism represents a novel species of a new genus, for which the name Ponticoccus litoralis gen. nov., sp. nov. is proposed. The type strain of Ponticoccus litoralis is CL-GR66(T) (=KCCM 90028(T) =DSM 18986(T)).