Micromonospora taraxaci sp nov., a novel endophytic actinomycete isolated from dandelion root (Taraxacum mongolicum Hand.-Mazz.)

A novel actinomycete, designated strain NEAU-P5(T), was isolated from dandelion root (Taraxacum mongolicum Hand.-Mazz.). Strain NEAU-P5(T) showed closest 16S rRNA gene sequence similarity to Micromonospora chokoriensis 2-19/6(T) (99.5 %), and phylogenetically clustered with Micromonospora violae NEAU-zh8(T) (99.3 %), M. saelicesensis Lupac 09(T) (99.0 %), M. lupini Lupac 14N(T) (98.8 %), M. zeae NEAU-gq9(T) (98.4 %), M. jinlongensis NEAU-GRX11(T) (98.3 %) and M. zamorensis CR38(T) (97.9 %). Phylogenetic analysis based on the gyrB gene sequence also indicated that the isolate clustered with the above type strains except M. violae NEAU-zh8(T). The cell-wall peptidoglycan consisted of meso-diaminopimelic acid and glycine. The major menaquinones were MK-9(H-8), MK-9(H-6) and MK-10(H-2). The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were C-16:0, iso-C-15:0 and C-17:0. Furthermore, some physiological and biochemical properties and low DNA-DNA relatedness values enabled the strain to be differentiated from members of closely related species. Therefore, it is proposed that strain NEAU-P5(T) represents a novel species of the genus Micromonospora, for which the name Micromonospora taraxaci sp. nov. is proposed. The type strain is NEAU-P5(T) (=CGMCC 4.7098(T) = DSM 45885(T)).