Isolated polynucleotide molecule, purified recombinant vector, prokaryotic host cell and mutated Streptomyces avermitilis cell, method for obtaining a new S. avermitilis strain and process for producing avermectins

摘要

The present invention relates to polynucleotide molecules comprising nucleotide sequences encoding an aveC gene product, which polynucleotide molecules can be used to alter the ratio or amount of class 2:1 avermectins produced in fermentation cultures of S. avermitilis. The present invention further relates to vectors, host cells, and mutant strains of S. avermitilis in which the aveC gene has been inactivated, or mutated so as to change the ratio or amount of class 2:1 avermectins produced.