Construction of genetically engineered strain producing 5-oxomilbemycin by knocking out milF in Steptomyces hygroscopicus HS023

Abstract:

Abstract:［Objective］ To construct a 5-oxomilbemycin producing strain by knocking out milF gene in Streptomyces hygroscopicus HS023． ［Methods］Plasmid pMSST-ΔmilF was constructed and introduced into milbemycin industrial strain Streptomyces hygroscopicus HS023，and milF mutant F2-18 was selected by PCR amplification．［Results］Fermentation experiments showed that no milbemycins was produced in F2-18，but 5-ketomilbemycin，the intermediate of milbemycin，was obviously accumulated，and the fermentation titer was enhanced．［Conclusion］ Genetically engineered strain can simplify the synthesis of milbemycin oxime and lepimectin chemical from milbemycin．