Biological synthesis of genistein in .

Genistein is a type of isoflavonoid found predominantly in leguminous plants. Genistein has diverse biological activities, such as anthelmintic and antioxidant effects, as well as inhibitory effects on the growth of several cancers. In addition, genistein is well known as a phytoestrogen. In this study, we attempted to biologically synthesize genistein from either -coumaric acid or naringenin using as a biotransformation host. Four genes, , , , and , were used for genistein production. To functionally express RcIFS and OsCPR, two members of the cytochrome P450 family, in , the membrane-binding anchor domain of each gene was removed, and and were translationally fused to generate an hybrid. Os4CL and PeCHS, or the RcIFS-OsCPR hybrid, were then transformed into BL21(DE3). Using these strains, we optimized our culture system at a laboratory scale in terms of the cell density, concentrations of substrate and isopropyl-β-D-thiogalactoside, temperature, and culture medium. Under the optimized culture conditions, genistein was produced at up to 35 mg/l and 18.6 mg/l using naringenin and -coumaric acid, respectively.