Micrococcus yunnanensis sp nov., a novel actinobacterium isolated from surface-sterilized Polyspora axillaris roots

In this study, strain YIM 65004(T), isolated from roots of Polyspora axillaris, was shown to represent a novel species of the genus Micrococcus by means of a polyphasic approach. Chemotaxonomic data gathered for peptidoglycan type, menaquinones, phospholipids and fatty acids strongly supported the classification of this strain within the genus Micrococcus: the cell-wall peptidoglycan contained lysine, glutamic acid, alanine, glycine and aspartic acid, the predominant menaquinones were MK-8(H-2) (66.97 %) and MK-7(H-2) (23.26 %), the phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unknown ninhydrin-negative phospholipid, and the major cellular fatty acids were anteiso-C-15:0 (61.98 %), iso-C-16:0 (14.25 %) and iso-C-15:0 (13.04 %). The G + C content of the genomic DNA was 71.7 mol%. A number of physiological features were found that clearly distinguished strain YIM 65004 T from recognized Micrococcus species. DNA-DNA hybridization studies suggested that the novel strain represents a separate genomic species. Based on the above data, a novel species of the genus Micrococcus, Micrococcus yunnanensis sp. nov., is proposed, with the type strain YIM 65004(T) (=CCTCC AA 208060(T)=DSM 21948(T)).