Proposal of Intrasporangium mesophilum sp. nov., and reclassification of Humihabitans oryzae Kageyama et al. 2007 as Intrasporangium oryzae comb. nov.

A gram-positive and aerobic bacterium, designated strain YIM 49065(T), was isolated from rhizospheric soil of Jatropha curcas in Yunnan, China. This isolate formed branched and fragmented mycelia containing ll-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The major cellular fatty acid profile was characterized by iso-C(14 : 0), iso-C(15 : 0) and iso-C(16 : 0), and the predominant menaquinone was MK-8(H(4)). The DNA G+C content was 69.6 mol%. A phylogenetic analysis based on 16S rRNA gene sequence demonstrated that strain YIM 49065(T) was closely associated with Intrasporangium calvum DSM 43043(T) and Humihabitans oryzae KV-657(T), exhibiting 98.8 % and 98.6 % 16S rRNA gene sequence similarities, respectively. Furthermore, DNA-DNA hybridizations among strains YIM 49065(T), I. calvum DSM 43043(T) and H. oryzae DSM 22331(T) indicated that this isolate represented a novel species in the genus Intrasporangium. On the basis of these data, we proposed one novel species, Intrasporangium mesophilum sp. nov., for strain YIM 49065(T) ( = DSM 23217(T)  = CCTCC AA 209077(T)). Additionally, the comparison of biochemical and phylogenetic characters supported the reclassification of Humihabitans oryzae as a separate species within the genus Intrasporangium, Intrasporangium oryzae comb. nov. (type strain KV-657(T)  = JCM 15924(T)  = NBRC 101802(T)  = NRRL B-24470(T)).