Dactylosporangium cerinum sp. nov., a novel actinobacterium isolated from the rhizosphere of Pinus koraiensis Sieb. et Zucc.

ABSTRACT

A novel actinobacterium, designated strain NEAU-TPG4(T) was isolated from rhizosphere soil of Pinus koraiensis Sieb. et Zucc. collected from Luobei, Heilongjiang Province, north China, and characterized using a polyphasic approach. Morphological and chemotaxonomic properties of strain NEAU-TPG4(T) were consistent with the description of the genus Dactylosporangium. The strain formed finger-shaped sporangia on short sporangiophores that emerged directly from substrate hyphae. The cell-wall peptidoglycan consisted of meso- and 3-hydroxy-diaminopimelic acids; arabinose, xylose and glucose were found as whole-cell sugars. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol. The predominant menaquinones were identified as MK-9(H8) and MK-9(H6). The predominant cellular fatty acids were identified as iso-C160, anteiso-C150, anteiso-C170 and C180. Phylogenetic analysis using 16S rRNA gene sequences also indicated that the strain should be classified in the genus Dactylosporangium and showed that the closest relatives were Dactylosporangium maewongense Japan Collection of Microorganism (JCM) 15933(T) (99.6 %), Dactylosporangium siamense NBRC 106093(T) (99.6 %), Dactylosporangium aurantiacum JCM 3083(T) (99.5 %) and Dactylosporangium luteum JCM 17685(T) (99.5 %). However, the low level of DNA-DNA relatedness and several cultural and physiological characteristics allowed the strain to be distinguished from its closest relatives. Thus, it is proposed that strain NEAU-TPG4(T) represents a novel Dactylosporangium species. Dactylosporangium cerinum sp. nov. The type strain of D. cerinum is NEAU-TPG4(T) (=CGMCC 4.7152(T) = DSM 46712(T)).