The Mutasynthetic Production of CHC-B1 from a Streptomyces avermitilis Mutant in the Presence of Cyclohexanecarboxylic Acid / 中国生物工程杂志

ABSTRACT

Gene deletion vector pLJ04(pKC1139∷bkdF+bkdH)was used to disrupt bkdFGH in Streptomyces avermitilis 76-02-e,an industrial producer of anthelmintic avermectin.The disruptants were confirmed by PCR.Shake flask experiment and HPLC analysis showed that the mutant lost the ability to produce avermectins.As it is expected,the mutant,named S.avermitilis bkd76-3,could restore the ability of producing avermectins when the feeding of methylbutyric acid and isobutyric acid to its fermentations was carried out.The addition of cyclohexanecarboxylic acid(CHC)into fermentations of the S.avermitilis bkd76-3 allowed for production of four components,two of which was confirmed as CHC-B1 and CHC-A2 by LC/MS analysis,respectively.