Amycolatopsis roodepoortensis sp. nov. and Amycolatopsis speibonae sp. nov.: antibiotic-producing actinobacteria isolated from South African soils

Two novel members of the genus Amycolatopsis were isolated from soil samples collected in South Africa. Strains JS72T and M29T clustered in the same clade in the 16S-rRNA, gyrB-16S-rRNA and gyrB-recN gene trees. Both strains showed anti-mycobacterial activity. The oxyB P450 monooxygenase B gene required for the production of glycopeptide antibiotics was detected in both strains, while strain JS72T was also shown to contain the 3-amino-5-hydroxy-benzoic acid synthase gene, which is required for the production of the ansamycin class of antibiotics. Genetic distance values (based on the gyrB and recN genes) were calculated between strains JS72T and M29T and their closest phylogenetic relatives. The values for strain JS72T were all above the threshold values of 0.02 and 0.04, respectively, that have been proposed to distinguish Amycolatopsis-type strains. The gyrB-based values for strain M29T were above the threshold for all but one strain; the recN-based values were all above the threshold. These data, along with DNA–DNA hybridization data, showed that strains JS72T and M29T belong to distinct genomic species. The physiological, phylogenetic and genetic distance data support the description of strains JS72T and M29T as the type strains of novel species, for which the names Amycolatopsis speibonae sp. nov. ( ¼ DSM 46660T ¼ NRRL B-24958T) and Amycolatopsis roodepoortensis sp. nov. ( ¼ DSM 46661T ¼ NRRL B-24959T) are proposed, respectively.PRM from the Medical Research Council of South Africa, the NRF (grant numbers: 2073133, 81014 and 85476) and the University Research Committee (University of Cape Town