Streptomyces siamensis sp. nov., and Streptomyces similanensis sp. nov., isolated from Thai soils

Abstract

Three actinomycete strains, KC-038 T, KC-031 and KC-106 T, were isolated from soil samples collected in the southern Thailand. The morphological and chemotaxonomic properties of strains KC-038 T, KC-031 and KC-106 T were consistent with the characteristics of members of the genus Streptomyces, that is, the formation of aerial mycelia bearing spiral spore chains; the presence of LL-diaminopimelic acid in the cell wall, MK-9 (H 6), MK-9 (H 4) and MK-9 (H 8) as the predominant menaquinones; and C 16:0, iso-C 16:0 and anteiso-C 15:0 as the major cellular fatty acids. 16S rRNA gene sequence analyses indicated that strains KC-038 T and KC-031 were highly similar (99.9%), and they were closely related to S. olivochromogenes NBRC 3178 T (98.1%) and S. psammoticus NBRC 13971 T (98.1%). Strain KC-106 T was closely related to S. seoulensis NBRC 16668 T (98.9%), S. recifensis NBRC 12813 T (98.9%), S. chartreusis NBRC 12753 T (98.7%) and S. griseoluteus NBRC 13375 T (98.4%). The values of DNA-DNA relatedness between the isolates and the type strains of the related species were below 70%. On the basis of the polyphasic evidence, the isolates should be classified as two novel species, namely Streptomyces siamensis sp. nov. (type strain, KC-038 T =NBRC 108799 T =PCU 328 T =TISTR 2107 T) and Streptomyces similanensis sp. nov. (type strain, KC-106 T =NBRC 108798 T =PCU 329 T =TISTR 2104 T). © 2013 Japan Antibiotics Research Association.