Streptomyces cavernae sp. nov., a novel actinobacterium isolated from a karst cave sediment sample.

A novel actinobacterial strain, designated SYSU K10008T, was isolated from a soil sample collected from a karst cave in Xingyi County, Guizhou Province, south-western PR China. The taxonomic position of the strain was investigated by using a polyphasic approach. Cells of the strain were aerobic, Gram-stain-positive and non-motile. On the basis of 16S rRNA gene sequence similarities and the results of phylogenetic analysis, strain SYSU K10008T was most closely related to Streptomyces cyaneus CGMCC 4.1671T, and shared the highest sequence identity of 98.3 % based on the NCBI database. In addition, ll-diaminopimelic acid was the diagnostic diamino acid in cell-wall peptidoglycan. The whole-cell sugars were glucose and rhamnose. The major isoprenoid quinone was MK-9(H6), while the major fatty acids (>10 %) were C16 : 0, iso-C16 : 0, anteiso-C15 : 0 and summed feature 3 (C16 : 1 ω7c/C16  : 1 ω6c). The polar lipids contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and one unidentified lipid. The genomic DNA G+C content of strain SYSU K10008T was 70.5 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU K10008T represents a novel species of the genus Streptomyces, for which the name Streptomyces cavernae sp. nov. is proposed. The type strain is SYSU K10008T (=KCTC 39850T=DSM 104115T).