Planifilum yunnanense sp. nov., a thermophilic thermoactinomycete isolated from a hot spring.

A thermophilic actinomycete, strain LA5(T), was isolated from a hot spring in Yunnan province, People's Republic of China. The isolate grew aerobically at temperatures of 50-75 degrees C. Aerobic mycelia were not observed. Single spores were produced along the substrate hypha. Strain LA5(T) was characterized chemotaxonomically by having MK-7 as the predominant menaquinone and iso-C(17 : 0) (27.7 %) and C(16 : 0) (22.4 %) as the major fatty acids. The cell wall contained meso-diaminopimelic acid. The DNA G+C content was 56.8 mol%. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain LA5(T) belongs to the genus Planifilum. Levels of DNA-DNA relatedness between strain LA5(T) and Planifilum fimeticola H0165(T) and Planifilum fulgidum 500275(T) were 43.6 and 52.7 %, respectively. On the basis of phenotypic properties and phylogeny, strain LA5(T) represents a novel species of the genus Planifilum, for which we propose the name Planifilum yunnanense sp. nov., with the type strain LA5(T) (=CCTCC AA206002(T)=KCTC 13052(T)).