POLYNUCLEOTIDE MOLECULE ENCODING PROTEIN-REGULATOR IN PRODUCING AVERMECTIN IN STREPTOMYCES AVERMITILIS (VARIANTS), CLONING VECTOR AND STRAIN COMPRISING THEREOF, METHOD FOR SCREENING MUTATIONS IN REGULATORY GENE, PREPARING GENETICALLY MODIFIED CELLS AND ENHANCEMENT OF AVERMECTINS CONTENT IN CULTURE Russian patent published in 2004 - IPC

FIELD: biotechnology, molecular biology, genetic engineering, microbiology. SUBSTANCE: invention relates to two genes (designated as ave R1 and ave R2) identified in Streptomyces avermitilis that encode polypeptides taking part in regulation of expression of enzyme avermectinpolyketide synthase and, respectively, in biosynthesis of avermectins. Using mutations resulting to inactivation of one or both above indicated genes cell cultures Streptomyces avermitilis characterizing with enhanced level of production of avermectins as compared with strains of "wild" type are prepared. Using the invention provides the enhancement of yield of streptomycetes strains used for production of antibiotics. Invention can be used in medicinal-biological industry in preparing avermectins. EFFECT: improved preparing method, valuable biological properties of strain and molecules. 21 cl, 7 dwg, 1 tbl, 9 ex