Polyphasic classification of the gifted natural product producer Streptomyces roseifaciens sp. nov.

A polyphasic study was designed to establish the taxonomic status of a Streptomyces strain isolated from soil from the QinLing Mountains, Shaanxi Province, China, and found to be the source of known and new specialized metabolites. Strain MBT76 T was found to have chemotaxonomic, cultural and morphological properties consistent with its classification in the genus Streptomyces. The strain formed a distinct branch in the Streptomyces16S rRNA gene tree and was closely related to the type strains of Streptomyces hiroshimensis and Streptomycesmobaraerensis. Multi-locus sequence analyses based on five conserved house-keeping gene alleles showed that strain MBT76 T is closely related to the type strain of S. hiroshimensis, as was the case in analysis of a family of conserved proteins. The organism was also distinguished from S. hiroshimensis using cultural and phenotypic features. Average nucleotide identity and digital DNA-DNA hybridization values between the genomes of strain MBT76 T and S. hiroshimensis DSM 40037 T were 88.96 and 28.4±2.3%, respectively, which is in line with their assignment to different species. On the basis of this wealth of data it is proposed that strain MBT76 T (=DSM 106196 T =NCCB 100637 T ), be classified as a new species, Streptomycesroseifaciens sp. nov.