Actinomadura rupiterrae sp. nov., isolated from cliff soil.

A novel actinomycete strain, designated CS5-AC15T, was isolated from a soil sample collected from a cliff on Mara Island, Jeju, Republic of Korea, and subjected to a polyphasic taxonomic analysis. The isolate produced well-developed, yellow substrate mycelium and white aerial mycelium that differentiated into straight or flexuous chains of smooth-surfaced spores. 16S rRNA gene sequence analyses showed that the organism belonged to the family Thermomonosporaceae and formed a tight cluster with the type strain of Actinomadura oligospora (97.4 % sequence similarity). Chemotaxonomic characteristics were consistent with its assignment to the genus Actinomadura in that the isolate had meso-diaminopimelic acid as the diagnostic diamino acid in the cell wall, madurose as the characteristic sugar, N-acetyl type of murein in the peptidoglycan, MK-9(H6) and MK-9(H8) as major menaquinones and a polar lipid profile containing diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and unknown phospholipids. Mycolic acids were not detected. The predominant fatty acids were C16:0, C18:1ω9c and iso-C16:0. The DNA G+C content was 70.9 mol%. DNA relatedness of strain CS5-AC15T and A. oligospora JCM 10648T was 37.9±0.7 %. On the basis of the phenotypic, phylogenetic and DNA-DNA hybridization data, strain CS5-AC15T is assigned to a novel species of the genus Actinomadura, for which the name Actinomadura rupiterrae sp. nov. is proposed (type strain CS5-AC15T=KCTC 19559T=DSM 45251T).