Herbidospora sakaeratensis sp. nov., isolated from soil, and reclassification of Streptosporangium claviforme as a later synonym of Herbidospora cretacea

An actinomycete strain, DMKUA 205(T), was isolated from a soil sample collected from the Sakaerat Biosphere Reserve in Nakhonratchasima Province, Thailand. The novel strain produced short chains of non-motile spores on the tips of long sporophores branching from the vegetative hyphae. The morphological and chemotaxonomic properties of this new isolate corresponded to those of members of the genus Herbidospora. Furthermore, 16S rRNA gene sequence analysis showed that the strain was closely related to members of the genus Herbidospora. Phenotypic properties and DNA-DNA relatedness values differentiated the new strain from its closest phylogenetic relatives Herbidospora yilanensis 0351M-12(T) (35-54% DNA-DNA relatedness) and Herbidospora daliensis 0385M-1(T) (58-65% relatedness). On the basis of phenotypic, genotypic and phylogenetic data, strain DMKUA 205(T) could be clearly distinguished from the type strains of H. yilanensis and H. daliensis. Therefore, strain DMKUA 205(T) represents a novel species, for which the name Herbidospora sakaeratensis sp. nov. is proposed. The type strain is strain DMKUA 205(T) (=BCC 11662(T) =NBRC 102641(T)). In addition, the DNA-DNA hybridization results from this study revealed that Streptosporangium claviforme is a later synonym of Herbidospora cretacea.