Tenggerimyces flavus sp. nov., isolated from soil in a karst cave, and emended description of the genus Tenggerimyces.

A novel actinomycete, designated strain S6R2A4-9(T), was isolated from a soil sample collected from a karst cave in Henan Province, China, and subjected to a polyphasic taxonomic study. This isolate grew optimally at 25-28 °C, pH 6.5-8.0 and in the absence of NaCl. The substrate mycelium of the isolate was well developed with irregular branches. Aerial mycelium fragmented into long, rod-shaped elements. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain S6R2A4-9(T) resided in the cluster of the genus Tenggerimyces within the family Nocardioidaceae and shared the highest 16S rRNA gene sequence similarity (98.98 %) with Tenggerimyces mesophilus I12A-02601(T). The G+C content of the genomic DNA was 67.0 mol%. The strain contained glucose, ribose and xylose in its whole-cell hydrolysates. Strain S6R2A4-9(T) possessed a novel variation of peptidoglycan derived from the type A1γ meso-Dpm-direct. The polar lipids consisted of diphosphatidylglycerol, N-acetylglucosamine-containing phospholipid, phosphatidylinositol mannoside, phosphatidylglycerol, phosphoglycolipids and glycolipids. The predominant menaquinones were MK-10(H6) and MK-10(H8). The major fatty acids were C16 : 0, iso-C16 : 0 and 10-methyl C17 : 0. The level of DNA-DNA relatedness between strain S6R2A4-9(T) and T. mesophilus I12A-02601(T) was 27.6 ± 3.0 %, which was low enough to indicate that the strain represents a distinct species of the genus Tenggerimyces. On the basis of the polyphasic taxonomic evidence, a novel species, Tenggerimyces flavus sp. nov., is proposed. The type strain of the novel species is S6R2A4-9(T) ( = DSM 28944(T) = CGMCC 4.7241(T)).