Biocatalytic conversion of avermectin to 4''-oxo-avermectin: improvement of cytochrome p450 monooxygenase specificity by directed evolution.

ABSTRACT: Discovery of the CYP107Z subfamily of cytochrome P450 oxidases (CYPs) led to an alternative biocatalytic synthesis of 4''-oxo-avermectin, a key intermediate for the commercial production of the semisynthetic insecticide emamectin. However, under industrial process conditions, these wild-type CYPs showed lower yields due to side product formation. Molecular evolution employing GeneReassembly was used to improve the regiospecificity of these enzymes by a combination of random mutagenesis, protein structure-guided site-directed mutagenesis, and recombination of multiple natural and synthetic CYP107Z gene fragments. To assess the specificity of CYP mutants, a miniaturized, whole-cell biocatalytic reaction system that allowed high-throughput screening of large numbers of variants was developed.

SUBMITTER: Trefzer A 

PROVIDER: S-EPMC1932781 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature