Potential antibiotic production of sp. nov., isolated from the root of .

Endophytic actinobacterial strain 3R004 was isolated from a root of collected in Thailand. In this report, the taxonomic position of this strain is described using a polyphasic approach. Based on the morphological characteristics and chemical composition of its cells, strain 3R004 was identified as a member of the genus . It produced a long chain of cylindrical spores on aerial mycelia. ll-Diaminopimelic acid was detected in the cell wall peptidoglycan. The menaquinones were MK-9(H), MK-9(H) and MK-9(H). C, iso-C, anteiso-C and iso-C were detected as the major cellular fatty acids. Polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and one unidentified lipid. Strain 3R004 showed the highest 16S rRNA gene similarity of 99.45 % to MK-45. The phylogenomic results indicated that strain 3R004 was close to GGCR-6 and DSM 40234. The DNA-DNA hybridization and average nucleotide identity values among strain 3R004 and closely related species were 35.5-63.1 % and 82.7-94.3 %, respectively. The type strain produced actinomycin D antibiotic as the major secondary metabolite. The maximum productivity of the actinomycin D (378 mg l) was observed when the strain was grown in 301 broth at 30 °C, 180 r.p.m. for 12 days. On the basis of phenotypic and genotypic evidence, strain 3R004 represents a novel species of the genus , for which the name is proposed. The type strain is 3R004 (=LMG 32138=TBRC 13128=NBRC 115065).