Streptomyces calidiresistens sp. nov., isolated from a hot spring sediment.

A Streptomyces-like actinomycete strain, designated as YIM 78087(T), was isolated from a sediment sample collected from Hehua hot spring in Tengchong, Yunnan province, south-west China. The taxonomic position of strain YIM 78087(T) was investigated by a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain YIM 78087(T) belongs to the genus Streptomyces and is closely related to Streptomyces fimbriatus DSM 40942(T), Streptomyces marinus DSM 41968(T) and Streptomyces qinglanensis DSM 42035(T) (97.18, 97.05 and 97.1 % similarity, respectively). Combined with the low values of DNA-DNA hybridization between strain YIM 78087(T) and its closest neighbours, these analyses indicated that this new isolate represents a different genomic species in the genus Streptomyces. The predominant menaquinones of strain YIM 78087(T) were identified as MK-9 (H4) and MK-9 (H6). The major fatty acids were identified as anteiso-C15:0 (28.4 %), anteiso-C17:0 (23.0 %) and iso-C16:0 (15.1 %). The whole-cell hydrolysates found to contain glucose, mannose and ribose. The DNA G+C content was determined to be 73.0 mol%. Based on the comparative analysis of phenotypic and genotypic characteristics, it is proposed that strain YIM 78087(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces calidiresistens sp. nov., is proposed. The type strain is YIM 78087(T) (=BCRC 16955(T)=DSM 42108(T)=JCM 19629(T)).