Roseovarius litoreus sp. nov., isolated from seawater of southern coast of Korean peninsula

Abstract

A gram-negative, non-flagellated and ovoid- to rod-shaped bacterial strain, designated GSW-M15(T), was isolated from seawater on the southern coast of South Korea. Strain GSW-M15(T) grew optimally at 30°C, at pH 7.0-7.5 and in the presence of 2 % (w/v) NaCl. The phylogenetic trees based on 16S rRNA gene sequences revealed that strain GSW-M15(T) belonged to the genus Roseovarius. Strain GSW-M15(T) exhibited highest 16S rRNA gene sequence similarity values (98.3 and 97.5 %) to Roseovarius halotolerans HJ50(T) and Roseovarius pacificus 81-2(T) and 92.8-96.2 % sequence similarity values to the type strains of the other Roseovarius species. Strain GSW-M15(T) contained Q-10 as the predominant ubiquinone and C(18:1) ω7c and 11-methyl-C(18:1) ω7c as the major fatty acids. The major polar lipids detected in strain GSW-M15(T) were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and two unidentified lipids. The DNA G+C content of strain GSW-M15(T) was 62.9mol% and its mean DNA-DNA relatedness values with R. halotolerans KCTC 22224(T) and R. pacificus LMG 24575(T) were 33 and 18 %, respectively. Differential phenotypic properties of strain GSW-M15(T), together with the phylogenetic and genetic distinctiveness, demonstrated that this strain is distinguishable from other Roseovarius species. On the basis of the data presented here, strain GSW-M15(T) (=KCTC 23897(T)=CCUG 62218(T)) represents a novel species of the genus Roseovarius, for which the name Roseovarius litoreus sp. nov. is proposed.