Flavonoids and stilbenes have attracted much
attention as potential targets for nutraceuticals,
cosmetics, and pharmaceuticals. We have de-veloped a system for producing ‘‘unnatural’’ fla-vonoids and stilbenes in Escherichia coli. The
artificial biosynthetic pathway included three
steps. These included a substrate synthesis
step for CoA esters synthesis from carboxylic
acids by 4-coumarate:CoA ligase, a polyketide
synthesis step for conversion of the CoA esters
into flavanones by chalcone synthase and chal-cone isomerase, and into stilbenes by stilbene
synthase, and a modification step for modifica-tion of the flavanones by flavone synthase, fla-vanone 3b -hydroxylase and flavonol synthase.
Incubation of the recombinant E. coli with exog-enously supplied carboxylic acids led to pro-duction of 87 polyketides, including 36 unnatu-ral flavonoids and stilbenes. This system is
promising for construction of a larger library
by employing other polyketide synthases and
modification enzyme