Nocardia aurantiaca sp. nov., isolated from soil in Thailand

A novel actinomycete strain, CT2-14^T, belonging to the genus Nocardia, was isolated from a soil sample collected from Phichit Province, Thailand. The taxonomic position of the strain was characterized using a polyphasic approach. The strain grew at 15-40 °C (optimum, 28-37 °C), pH 6-11 (optimum, pH 6-8) and on an International Streptomyces Project 2 with 4 % (w/v) NaCl agar plate. Meso-diaminopimelic acid was detected in the cell-wall peptidoglycan. Ribose, arabinose and galactose were detected in its whole-cell hydrolysates. Mycolic acids were present. The strain contained C_16 : 0, summed feature 3, C_17 : 0 10-methyl and C_18 : 1 ω9c as the major fatty acids and MK-8(H₄ω-cycl) as the major menaquinone. The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylinositol mannosides. Strain CT2-14^T showed the highest 16S rRNA gene similarity to Nocardia veterana JCM 11307^T (98.4 %), Nocardia africana JCM 11438^T (98.2 %) and Nocardia kruczakiae JCM 13032^T (98.0 %). The draft genome of strain CT2-14^T was 7.37 Mb with 6685 coding sequences with an average G+C content of 67.9 mol %. Based on the phylogenomic tree analysis, the strain was closely related to Nocardia niigatensis NBRC 100131^T. On the basis of polyphasic and genome analyses, strain CT2-14^T represented a novel species of the genus Nocardia for which the name Nocardia aurantiaca sp. nov. is proposed. The type strain is CT2-14^T (=JCM 33775^T=TISTR 2838^T).