Actinomadura meridiana sp. nov., isolated from mountain soil.

A novel actinomycete, designated strain DLS-45(T), was isolated from soil from the surface of a rock collected from the peak of Darangshi Oreum (Small Mountain) in Jeju, Republic of Korea. Substrate mycelium was well developed, but aerial mycelium was scant on most of the media tested. Spherical to subspherical spores on the aerial mycelium were in chains that were arranged in hooks and their surfaces were warty. The combination of morphological and chemical features supported the classification of the new isolate in the genus Actinomadura. The neighbour-joining tree based on 16S rRNA gene sequences showed that the strain belonged to the family Thermomonosporaceae and formed a coherent cluster with Actinomadura pelletieri IMSNU 22169(T) (98.0% sequence similarity). The other closest relatives were Actinomadura bangladeshensis 3-46-b(3)(T) (98.2%) and Actinomadura chokoriensis 3-25-a(11)(T) (97.9%). Levels of DNA-DNA relatedness between strain DLS-45(T) and the type strains of the phylogenetic relatives were less than 17%. A battery of phenotypic, genotypic and DNA-DNA relatedness data indicated that strain DLS-45(T) represented a novel species of the genus Actinomadura, for which the name Actinomadura meridiana sp. nov. is proposed. The type strain is strain DLS-45(T) (=KCTC 19558(T)=DSM 45252(T)).