Ruegeria halocynthiae sp. nov., isolated from the sea squirt Halocynthia roretzi

Abstract

A Gram-negative, non-motile, rod-shaped bacterial strain, designated MA1-6 T , was isolated from a sea squirt ( Halocynthia roretzi ) collected from the South Sea, Korea, and was characterized to determine its taxonomic position. Strain MA1-6 T grew optimally at pH 7.0–8.0, at 30 °C and in the presence of 2–3 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MA1-6 T fell within the clade comprising Ruegeria species and exhibited 95.3–96.5 % similarity to the type strains of recognized Ruegeria species. Strain MA1-6 T contained Q-10 as the predominant ubiquinone and C 18 : 1 ω7 c as the major fatty acid, which is consistent with data for Ruegeria species. The major polar lipids detected in strain MA1-6 T and Ruegeria atlantica KCTC 12424 T were phosphatidylcholine, phosphatidylglycerol, an unidentified aminolipid and an unidentified lipid. The DNA G+C content of strain MA1-6 T was 58.6 mol%. Differential phenotypic properties, together with phylogenetic distinctiveness, demonstrated that strain MA1-6 T can be distinguished from recognized Ruegeria species. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain MA1-6 T is considered to represent a novel species of the genus Ruegeria , for which the name Ruegeria halocynthiae sp. nov. is proposed; the type strain is MA1-6 T ( = KCTC 23463 T = CCUG 60744 T ).