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 77924^T, 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 77924^T belongs to the genus Thermus. The 16S rRNA gene sequence similarity values between strain YIM 77924^T and other species of the genus Thermus were all below 97 %. The polar lipids of strain YIM 77924^T 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-C_16:0, iso-C_15:0, iso-C_17:0 and C_16:0. On the basis of the morphological and chemotaxonomic characteristics as well as genotypic data, strain YIM 77924^T is proposed to represent a novel species, Thermus tengchongensis sp. nov., in the genus Thermus. The type strain is YIM 77924^T (=KCTC 32025^T = CCTCC AB2012063^T).