Thermus tengchongensis sp. nov., isolated from a geothermally heated soil sample in Tengchong, Yunnan, south-west China

A Gram-stain negative aerobic bacterium, designated YIM 77924T, was isolated from a geothermally heated soil sample collected at Rehai National Park, Tengchong, Yunnan province, south-west China. Growth was found to occur from 55 to 75 °C (optimum 65 °C), pH 6.0–8.0 (optimum pH 7.0) and 0–1 % NaCl (w/v). Cells were observed to be rod-shaped and the colonies convex, circular, smooth, yellow and non-transparent. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain YIM 77924T belongs to the genus Thermus. The 16S rRNA gene sequence similarity values between strain YIM 77924T and other species of the genus Thermus were all below 97 %. The polar lipids of strain YIM 77924T were determined to be aminophospholipid, phospholipid and glycolipid. The predominant respiratory quinone was determined to be MK-8 and the G+C content was 66.64 mol%. The major fatty acids identified were iso-C16:0, iso-C15:0, iso-C17:0 and C16:0. On the basis of the morphological and chemotaxonomic characteristics as well as genotypic data, strain YIM 77924T is proposed to represent a novel species, Thermus tengchongensis sp. nov., in the genus Thermus. The type strain is YIM 77924T (=KCTC 32025T = CCTCC AB2012063T).