sp. nov., an actinomycete isolated from cave soil in Thailand.

A novel actinobacterium, designated strain NN258, was isolated from a cave soil sample collected from a karst cave at Khao No-Khao Kaeo, Nakhon Sawan province, Thailand. The morphological, chemotaxonomic and phylogenetic characteristics were consistent with its classification in the genus . Strain NN258 showed the highest 16S rRNA gene sequence similarity values to HMC10, 6K102, DSM 43768, KC712 and IFO 14681. The strain formed an extensively branched substrate and aerial mycelia. The whole-cell hydrolysates contained -diaminopimelic acid as the diagnostic diamino acid, with glucose, madurose, mannose and ribose as the whole-cell sugars. The polar lipids were diphosphatidylglycerol, phosphotidylmethylethanolamine, phosphatidylethanolamine, hydroxy-phosphatidylmonomethylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, two unidentified phospholipids, three unidentified sugar-containing phosphoaminolipids, an unidentified glycolipid and two unidentified lipids. The predominant menaquinone was MK-9(H), with minor amounts of MK-9(H), MK-9(H) and MK-9(H). Major cellular fatty acids (>10%) were iso-C and 10-methyl-C. The G+C content of the genomic DNA was 71.0 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain NN258 and the reference strains were 79.9-80.9 % and 26.1-27.0 %, respectively. On the basis of phenotypic, genotypic and phylogenetic data, strain NN258 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is NN258 (=TBRC 11478=NBRC 114269).