Metabolic engineering of Escherichia coli to produce plant specific secondary metabolites from aromatic amino acids

Abstract

Plants are known for producing diversified metabolites that are exclusively identified from plant sources. These plant-specific metabolites have been demonstrated to perform actively in signal transmission to assist plants growth under exogenous stress. This category of natural compounds attracts more attention beyond their roles in plants for their health promoting capabilities and medicinal potentials. However, commercialization of synthetic technology towards these therapeutic candidates is yet to be developed for their insufficient availability from native origins and uneconomical chemical approaches. In order to engineer more cost-effective alternatives of yielding these valuable metabolites, microbial production has been established by exploiting plant genes and enzymes to construct artificial synthetic pathway towards end products in categories of alkaloids, phenylpropanoids and isoprenoids. Caffeic acid, as a target compound in research, was produced in metabolically engineered E. coli. Highest titers from de novo production of caffeic acid and one-step conversion were achieved in this work.