Role of the snorA gene in nogalamycin biosynthesis by strain Streptomyces nogalater Lv65

Streptomyces nogalater Lv65 (= IMET 43360) is a producer of the anthracycline antitumor anti biotic nogalamycin. In this work, some aspects of the regulation of nogalamycin production by this strain were studied. Insertional inactivation of the snorA gene in the chromosome of the nogalamycin producer was car ried out; as a result, strain S. nogalater A1 was obtained. This is the first successful gene knockout in S. nogalater. It was demonstrated that strain A1 is characterized by the absence of synthesis of nogalamycin and its precursors, as well as by the inability to form spores. As a result of the knockout complementation with an entire copy of the snorA gene, resumption of the nogalamycin synthesis by strain S. nogalater A1 was observed; in the case of the wildtype strain S. nogalater Lv65, insertion resulted in an increase in the antibiotic synthe sis. Obtained results indicate that the snorA gene is involved in positive regulation of nogalamycin biosynthe sis. Keywords: antibiotics, nogalamycin, Streptomyces nogalater, SARP regulators, snorA. DOI: 10.1134/S0026261711040096