Maribius salinus gen. nov., sp. nov., isolated from a solar saltern and Maribius pelagius sp. nov., cultured from the Sargasso Sea, belonging to the Roseobacter clade

Abstract

Two strictly aerobic, Gram-negative bacteria, designated strains CL-SP27T and B5-6T, were isolated from the hypersaline water of a solar saltern in Korea and from the surface water of the Sargasso Sea, respectively. The two strains were rod-shaped, non-motile and grew on marine agar 2216 as beige colonies. Phylogenetic analyses of 16S rRNA gene sequences revealed a clear affiliation of the novel strains to the family Rhodobacteraceae. However, the novel strains were only distantly related to members of the Roseobacter clade, forming a distinct lineage. Although the 16S rRNA gene sequence similarity between strains CL-SP27T and B5-6T was very high (99.6 %), DNA–DNA relatedness between the strains was 48.4 %, suggesting that the strains be categorized as two genospecies. Additionally, the two novel strains could be differentiated by DNA G+C contents, fatty acid profiles, carbon source utilization patterns, antibiotic susceptibilities and biochemical characteristics. Based on taxonomic data obtained in this study, strains CL-SP27T and B5-6T represent separate species within a novel genus of the family Rhodobacteraceae, for which the names Maribius salinus gen. nov., sp. nov. (type species) and Maribius pelagius sp. nov. are proposed. The type strains of Maribius salinus and Maribius pelagius are CL-SP27T (=KCCM 42113T=JCM 13037T) and B5-6T (=KCCM 42336T=JCM 14009T), respectively.