Heterologous Biosynthesis Of Glucosinolates In Escherichia Coli

Currently, cancer is a serious threat to human health. The natural anticancer drug sulforaphane can convert carcinogens into non-carcinogens by reducing the metabolic level of I enzyme. Glucosinolate can be hydrolyzed by myrosinase to sulforaphane. Thus, glucosinolates are one of the essential substances in the process of sulforaphane production.This study is aimed at achieving glucosinolate biosynthesis in Escherichia coli. In this study the following goals have been achieved.We searched the databases KEGG, NCBI and BREADA to redesign a heterologous glucosinolate biosynthesis pathway in Escherichia coli, and design three expression modules to improve the product yield.Cloned and expressed the five genes livE, leuC, leuD, leuB and MAM1 involved in the upstream module to realize the over-expression and heterologous-expression in E.coli. Then we successfully detected the activity of transaminase B and MAM1.Constructed the recombinant plasmid pZE-IivE-MAM1-IeuC-leuD-leuB, then transformed them into the host for fermentation. We detected the product of upstream module with LC-MS.In order to block the accumulation of the main by-product acetate, we knocked out gene ackA of the host bacterium JM109.