Streptomyces specialis sp. nov.

A Gram-positive, non-endospore-forming bacterium (GW41-1564T) was isolated from soil. Comparison of 16S rRNA gene sequences showed that strain GW41-1564T is a member of the genus Streptomyces, exhibiting highest similarities with Streptomyces hainanensis YIM 47672T (97.8 %) and Streptomyces cacaoi subsp. cacaoi NBRC 12748T (97.5 %). Strain GW41-1564T could be distinguished from any other Streptomyces species with validly published names by sequence similarity values less than 97.5 %. Strain GW41-1564T exhibited an unusual quinone system, with the predominant compounds MK-10(H4) and MK-10(H6) and smaller amounts of MK-9(H4) and MK-9(H6). The type strain of the most closely related species, S. hainanensis YIM 47672T, also contained an unusual quinone system composed of MK-9(H6) and MK-9(H8) in addition to MK-9(H4) and MK-10(H0), whereas the type strain of the second most closely related species, S. cacaoi NBRC 12748T, contained a quinone system, composed of MK-9(H6) and MK-9(H8), typical of Streptomyces. The polar lipid profile of GW41-1564T consisted of the predominant compound diphosphatidylglycerol, moderate amounts of phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol and minor to trace amounts of two phosphatidylinositol mannosides and several unknown lipids, and the major fatty acids were iso-C16 : 0, anteiso-C17 : 1 ω9c and anteiso-C17 : 0. The results of physiological and biochemical tests allowed further phenotypic differentiation of strain GW41-1564T from the related species S. hainanensis. Strain GW41-1564T clearly merits species status, and we propose the name Streptomyces specialis sp. nov., with the type strain GW41-1564T (=DSM 41924T =CCM 7499T).