Biosynthesis of rubradirin as an ansamycin antibiotic from Streptomyces achromogenes var. rubradiris NRRL3061.

The four overlapping cosmids from the rubradirin producer , Streptomyces achromogenes var rubradiris NRRL 3061, have 58 ORFs within a 105.6 kb fragment. These ORFs harbored essential genes responsible for the formation and attachment of four distinct moieties, along with the genes associated with regulatory, resistance, and transport functions. The PKS ( rubA) and glycosyltransferase ( rubG2) genes were disrupted in order to demonstrate a complete elimination of rubradirin production. The rubradirin biosynthetic pathway was proposed based on the putative functions of the gene products, the functional identification of sugar genes, and the mutant strains. [ABSTRACT FROM AUTHOR]