Spirosoma litoris sp. nov., a bacterium isolated from beach soil

A Gram-stain-negative, non-motile, non-spore-forming, rod-shaped, aerobic bacterium, designated 15J16-2T3A^T, was isolated from beach soil on Jeju Island, South Korea. Strain 15J16-2T3A^T grew at 10-37 °C (optimum growth at 25 °C) and pH 6.5-8.5 (optimum growth at pH 7). Based on 16S rRNA gene phylogenetic analysis, the novel strain was closely related to members of the genus Spirosoma(94.8-89.9 % similarities) and formed a separate branch within the genus together with Spirosoma luteolum 16F6E^T in neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees. The G+C content of the genomic DNA of strain 15J16-2T3A^T was 47.6 mol%. The detection of menaquinone MK-7 as the predominant respiratory quinone, a fatty acid profile with summed feature 3 (C16 : 1ω7c/C16 : 1ω6c; 35.5 %), C16 : 1ω5c (26.6 %), and iso C15 : 0 (10.1 %) as the major components, phosphatidylethanolamine and unidentified aminophospholipid as the major polar lipids also support the affiliation of strain 15J16-2T3A^T with the genus Spirosoma. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain 15J16-2T3A^T from members the genus Spirosoma. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain 15J16-2T3A^T represents a novel species of the genus Spirosoma, for which the name Spirosoma litoris sp. nov. is proposed. The type strain is 15J16-2T3A^T (=KCTC 52029^T=JCM 31999^T).