Oceanospirillum nioense sp. nov., a marine bacterium isolated from sediment sample of Palk bay, India.

A novel Gram-negative, spiral shaped, motile bacterium, designated strain NIO-S6(T), was isolated from a sediment sample collected from Off-shore Rameswaram, Tamilnadu, India. Strain NIO-S6(T) was found to be positive for oxidase, DNase and lysine decarboxylase activities and negative for catalase, gelatinase, lipase, ornithine decarboxylase, nitrate reductase, aesculinase, amylase and urease activities. The fatty acids were determined to be dominated by C10:0 3OH, C16:0, C16:1 and C18:1. Strain NIO-S6(T) contains Q-8 as the major respiratory quinone. The DNA G+C content of the strain NIO-S6(T) was determined to be 49.5 ± 0.6 mol %. Phylogenetic analysis based on 16S rRNA gene sequence of strain NIO-S6(T) indicated Oceanospirillum linum and Oceanospirillum maris of the family Oceanospirillaceae (phylum Proteobacteria) are the closest related species with sequence similarities of 98.4 and 97.8 % respectively. Other members of the family showed sequence similarities <96.4 %. However, DNA-DNA hybridization with Oceanospirillum linum LMG 5214(T) and Oceanospirillum maris LMG 5213(T) showed a relatedness of 31.5 and 46.9 % with respect to strain NIO-S6(T). Based on the phenotypic characteristics and on phylogenetic inference, strain NIO-S6(T) is proposed as a novel species of the genus Oceanospirillum as Oceanospirillum nioense sp. nov. and the type strain is NIO-S6(T) (=MTCC 11154(T) = KCTC 32008(T)).