초록
<P><B>Abstract</B></P> <P>Caffeic acid has been widely recognized as a versatile pharmacophore for synthesis of new chemical entities, among which caffeic acid derived phenethyl esters and amides are the most extensively-investigated bioactive compounds with potential therapeutical applications. However, the natural biosynthetic routes for caffeic acid derived phenethyl esters or amides remain enigmatic, limiting their bio-based production. Herein, product-directed design of biosynthetic schemes allowed the development of thermodynamically favorable pathways for these compounds <I>via</I> acyltransferase (ATF) mediated trans-esterification. Production based screening identified a microbial O-ATF from <I>Saccharomyces cerevisiae</I> and a plant N-ATF from <I>Capsicum annuum</I> capable of forming caffeic acid derived esters and amides, respectively. Subsequent combinatorial incorporation of caffeic acid with various aromatic alcohol or amine biosynthetic pathways permitted the <I>de novo</I> bacterial production of a panel of caffeic acid derived phenethyl esters or amides in <I>Escherichia coli</I> for the first time. Particularly, host strain engineering <I>via</I> systematic knocking out endogenous caffeoyl-CoA degrading thioesterase and pathway optimization <I>via</I> titrating co-substrates enabled production enhancement of five caffeic acid derived phenethyl esters and amides, with titers ranging from 9.2 to 369.1mg/L. This platform expanded the capabilities of bacterial production of high-value natural aromatic esters and amides from renewable carbon source <I>via</I> tailoring non-natural biosynthetic pathways.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Acyltransferases for synthesis of caffeic acid esters and amides were identified. </LI> <LI> Caffeic acid phenethyl esters and amides were produced from glucose in <I>E. coli</I>. </LI> <LI> Production improvement was made by up to 3-fold <I>via</I> host and pathway optimization. </LI> </UL> </P>