Spirosoma aerophilum sp nov., isolated from an air sample

A rod-shaped, yellow, Gram-stain-negative, non-flagellated, aerobic bacterium, designated 5516J-17(T), was isolated from an air sample collected from Jeju Island, Republic of Korea. It grew in the temperature range of 10-37 degrees C (optimum 28-30 degrees C), pH 6.0-11.0 (optimum, pH 7.0) and 0-1 % NaCl (w/v). Phylogenetic trees generated using 16S rRNA gene sequences revealed that strain 5516J-17(T) belongs to the genus Spirosoma, showing 96.9% sequence similarity to the most closely related species, Spirosoma linguale DSM 74(T). The cellular fatty acids comprised large amounts (>10% of total fatty acids) of summed feature 3 (C-16:1 omega 7c and/or C-16:1 omega 6c) and C-16:1 omega 5c, and moderate amounts (5-10% of total fatty acids) of iso-C-17:0 3-OH, iso-C-15:0 and C-16:0. The DNA G+C content was 55.7 mol % and MK-7 was the predominant isoprenoid quinone. Polar lipids were phosphatidylethanolamine, two unknown aminophospholipids, one unknown aminolipid and one unknown lipid. On the basis of this phenotypic and polyphasic taxonomy study, it is suggested that strain 5516J-17(T) represents a novel species within the genus Spirosoma, with the proposed name Spirosoma aerophilum. The type strain is 55161-17(T) (= KACC 17323(T) = DSM 28388(T) = JCM 19950(T)).