Two novel Gram-stain-positive, irregular rod-shaped bacterial strains, dk3136T and dk3543, were isolated from the faeces of Tibetan gazelle (Procapra picticaudata) in the Qinghai-Tibet Plateau of PR China. The cells were aerobic, oxidase-negative and catalase-positive. Colonies were yellowish, circular without any observable aerial mycelium after culturing at 28 ℃ for 3 days on brain-heart infusion (BHI) agar with 5 % sheep blood. The cells grew optimally at 28 °C, pH 7.5 and with 1 % (w/v) NaCl on BHI agar supplemented with 5 % sheep blood. Phylogenetic analysis of the 16S rRNA gene sequences revealed that their nearest phylogenetic relative was Nocardioides solisilvae Ka25T (97.9 % similarity). The results of 16S rRNA gene sequence and phylogenetic/phylogenomic analyses illustrated that N. solisilvae Ka25T, Nocardioides gilvus XZ17T, Nocardioides houyundeii 78T and Nocardioides daphniae D287T were their nearest phylogenetic neighbours. The DNA G+C contents of strains dk3136T and dk3543 were 70.3 mol% and 70.4 mol%, respectively. Their genomes exhibit lower than threshold (95-96 %) average nucleotide identity to known species of the genus Nocardioides. ll-2,6-diaminopimelic acid was the diagnostic diamino acid and MK-8(H4) was the predominant respiratory quinone. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The two strains had C18 : 1 ω9c, iso-C16 : 0 and C17 : 1 ω8c as the major fatty acids, and rhamnose and galactose as the main whole-cell sugars. On the basis of the results of our genotypic, phenotypic and biochemical analyses, we conclude that strains dk3136T and dk3543 represent a novel species in genus Nocardioides, for which the name Nocardioides jishulii sp. nov. is proposed. The type strain is dk3136T (=CGMCC 4.7570T=JCM 33496T=KCTC 49314T).
Keywords: Nocardioides; Qinghai–Tibet Plateau; Tibetan gazelle; novel species.