Sphaerisporangium corydalis sp. nov., isolated from the root of Corydalis yanhusuo L.

Two Gram-stain positive, aerobic actinomycete strains, designated NEAU-YHS12 and NEAU-YHS15(T), were isolated from the root of Corydalis yanhusuo L. collected from Wuchang, Heilongjiang Province, northeast China. Phylogenetic analysis of 16S rRNA gene sequences showed that the two strains are closely related to one another (99.8 % similarity), and had the closest relationship with Sphaerisporangium cinnabarinum JCM 3291(T) (98.7, 98.6 %), Sphaerisporangium flaviroseum YIM 48771(T) (98.6, 98.6 %), Sphaerisporangium melleum JCM 13064(T) (98.5, 98.4 %) and Sphaerisporangium dianthi NEAU-CY18(T) (98.4, 98.4 %). DNA-DNA hybridization value between strains NEAU-YHS12 and NEAU-YHS15(T) was 82 ± 1.4 %, and the values between the two strains and the closely related type strains were well below 70 %. The two strains also shared a number of phenotypic characteristics that were distinct from the closely related species. Both strains were observed to contain MK-9(H6), MK-9(H4) and MK-9(H2) as the detected menaquinones. The cell wall peptidoglycan was found to contain meso-diaminopimelic acid. The phospholipid profiles were found to contain diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, phosphoglycolipid, and an unidentified phospholipid. The major fatty acids were identified as iso-C16:0, C17:1 ω7c, C18:0 and iso-C15:0. On the basis of the genetic and phenotypic properties, it is proposed that strains NEAU-YHS15(T) and NEAU-YHS12 be classified as representatives of a novel species of the genus Sphaerisporangium, for which the name Sphaerisporangium corydalis sp. nov is proposed. The type strain is NEAU-YHS15(T) (CGMCC 4.7148(T) = DSM46732(T)).