Nocardioides xinjiangensis sp. nov., a novel species isolated from desert soil

Abstract

Two novel strains, SYSU D00514^T and SYSU D00778, were isolated from desert soil in the Gurbantunggut Desert, Xinjiang Uygur Autonomous Regions, PR China. SYSU D00514^T and SYSU D00778 were aerobic, Gram-stain-positive, rod-shaped, catalase-positive and oxidase-negative. SYSU D00514^T grew at temperatures ranging from 4 to 37 °C (optimum, 28–30 °C), at pH 6.0–8.0 (optimum, 7.0), and tolerated NaCl concentrations from 0 to 7.5% (optimum, 0.5% w/v). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains SYSU D00514^T and SYSU D00778 were closely related to the members of the genus Nocardioides. Two isolates were most closely related to Nocardioides alpinus Cr7-14 ^T (98.05% and 98.19%). The G + C content of the genomic DNA of strains SYSU D00514^T and SYSU D00778 were both 72.8%. Strain SYSU D00514^T and the type strains of the genus Nocardioides in the analysis had average nucleotide identity values of 76.8–85.8% as well as digital DNA–DNA hybridization values between 19.5% and 28.0%. The predominant cellular fatty acids of strain SYSU D00514^T were C_17:1 ω8c, C_18:1 ω9c and iso-C_16:0. For strain SYSU D00514^T, the major polar lipids encompassed diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylinositol, an unidentified aminophospholipid and two unidentified aminolipids. The main respiratory quinone of strain SYSU D00514^T was MK-8 (H4). Based on the results of polyphasic taxonomic experiments, we propose that strains SYSU D00514^T and SYSU D00778 represent a novel species of the genus Nocardioides, with the name Nocardioides xinjiangensis. The type strain is SYSU D00514^T (= CGMCC 1.18622 ^T = MCCC 1K05001^T = KCTC 49488 ^T).