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 JS72(T) and M29(T) 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 JS72(T) 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 JS72(T) and M29(T) and their closest phylogenetic relatives. The values for strain JS72(T) 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 M29(T) 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 JS72(T) and M29(T) belong to distinct genomic species. The physiological, phylogenetic and genetic distance data support the description of strains JS72(T) and M29(T) as the type strains of novel species, for which the names Amycolatopsis speibonae sp. nov. (=DSM 46660(T)=NRRL B-24958(T)) and Amycolatopsis roodepoortensis sp. nov. (=DSM 46661(T)=NRRL B-24959(T)) are proposed, respectively.