Spirosoma daeguensis sp. nov., isolated from beach soil

A Gram-stain-negative, non-motile, non-spore-forming, rod-shaped, aerobic bacterium, designated 15J9-6^T, was isolated from beach soil on Jeju Island, South Korea. Strain 15J9-6^T, grew at 10–30°C (optimum growth at 25°C) and pH 7–8 (optimum growth at pH 7) on R2A, NA, and TSA agar. Phylogenetically, the strain was closely related to members of the genus Spirosoma (92.3–90.1% 16S rRNA gene sequence similarities) and showed highest sequence similarity to Spirosoma panaciterrae DSM 21099^T (92.3%). The G+C content of the genomic DNA of strain 15J9-6^T was 45.7 mol%. The strain contained phosphatidylethanolamine, two unidentified aminophospholipids, an unidentified phospholipid, and an unidentified lipid as the major polar lipids; menaquinone MK-7 as the predominant respiratory quinone and summed feature 3 (C_16:1ω6c/C_16:1ω7c; 30.1%), C_16:1ω5c (23.1%), iso C_15:0 (13.3%), and C_16:0 (8.4%) as the major fatty acids which supported the affiliation of strain 15J9-6^T to the genus Spirosoma. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain 15J9-6^T from recognized Spirosoma species. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain 15J9-6^T represents a novel species of the genus Spirosoma, for which the name Spirosoma daeguensis sp. nov. is proposed. The type strain is 15J9-6^T (=KCTC 52036^T =JCM 31995T).