Reclassification of a reveromycin-producer and the proposals of Actinacidiphila reveromycinica sp. nov. and Actinacidiphila acidipaludis comb. nov.

Abstract

Streptomyces sp. SN-593, a reveromycin producer, was previously thought to belong to the genus Streptomyces based on its morphological and chemotaxonomic characteristics. In this paper, we re-considered its taxonomic position according to the current criteria. Phylogenetic analysis using 16S rRNA gene sequences showed that the strain belongs to the genus Actinacidiphila. In multilocus sequence and phylogenomic analyses, the strain SN-593 represented a distinct evolutionary lineage within this genus, and its closest neighbor was A. yanglinensis. Digital DNA-DNA hybridization indicated that the strain shares less than 32% DNA-DNA relatedness with the type strains of closely related species, confirming this strain is a novel genomospecies. According to its phenotypic distinctiveness from the closest neighbor, we propose Actinacidiphila reveromycinica sp. nov. for the strain SN-593T. Additionally, as Streptomyces acidipaludis belonged to the genus Actinacidiphila in these analyses, it should be transferred to the genus, for which Actinacidiphila acidipaludis comb. nov. is proposed.