Spirosoma metallum sp. nov., isolated from an automobile air conditioning system

A Gram-stain-negative and yellow-pigmented bacterial strain, designated TX0653T, was isolated from an automobile evaporator core collected in Korea. The cells were aerobic and rod-shaped. The strain grew at 10−28 °C (optimum, 25 °C), at pH 6.0−7.5 (optimum, 6.5), and in the presence of 0−1% (w/v) NaCl (optimum, 0%). Phylogenetically, the strain was related to members of the genus Spirosoma (95.1−90.8% 16S rRNA sequence similarity) and distantly related to Spirosoma pulveris JSH5-14T (95.1%), Spirosoma fluviale MSd3T (95.0%), Spirosoma endophyticum DSM 26130T (94.8%), and Spirosoma linguale DSM 74T (94.6%). The major fatty acids of the strain were summed feature 3 (C16:1ω6c and/or C16:1ω7c), C16:1ω5c, iso-C15:0, iso-C17:0 3-OH, and C16:0. MK-7 was identified as the predominant menaquinone. The polar lipids profile indicated the presence of one phosphatidylethanolamine, one unidentified aminolipid, one unidentified aminophospholipid, two unidentified phospholipids, and three unidentified lipids. On the basis of the phenotypic, genotypic, and chemotaxonomic characteristics, strain TX0653T represents a novel species in the genus Spirosoma, for which the name Spirosoma metallum sp. nov. (= KACC 19278T = NBRC 112495T) is proposed.