Roseovarius salinarum sp. nov., isolated from a marine solar saltern

A Gram-stain-negative, rod-shaped, non-motile and halophilic bacterium, designated N53 , was isolated from a marine solar saltern in Wendeng, China. Cells of strain N53 were 0.3-0.4 µm wide and 2.0-5.5 µm long, catalase-positive and oxidase-positive. The bacterium grew optimally at 33 °C, at pH 7.0-8.0 and in the presence of 6.0 % (w/v) NaCl. Bacteriochlorophyll a was not found. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain N53 formed a phylogenetic lineage with members of the genus Roseovarius. Strain N53 exhibited the highest levels of similarity to Roseovarius pacificus (94.6 %) and Roseovarius confluentis (94.6 %), with a lower level to Roseovarius tolerans was 94.0 %. The percentage of conserved proteins and average nucleotide identity values between N53 and the type strain of the type species, Roseovarius tolerans, were 66.1 and 76.4 %, respectively. The genomic DNA G+C content was 68.1 mol%. The sole respiratory quinone was ubiquinone-10. The predominant cellular fatty acids (>10 %) were C18 : 1ω7c (54.0 %) and C16 : 0 (17.9 %). The polar lipids of strain N53 consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid, two unidentified phospholipids and two unidentified glycolipids. The differential phenotypic properties, together with the chemotaxonomic and genomic distinctiveness, revealed that strain N53 was separate from other recognized species of the genus Roseovarius. On the basis of the data presented here, strain N53 represents a novel species of the genus Roseovarius, for which the name Roseovariussalinarum sp. nov. is proposed. The type strain is N53 (=MCCC 1H00200 =KCTC 52886 ).