Engineered Biosynthesis of Alkyne-Tagged Polyketides by Type I PKSs

• Main Authors: William B. Porterfield, Nannalin Poenateetai, Wenjun Zhang
• Format: Article
• Language: English
• Published: Elsevier 2020-03-01
• Series: iScience
• Online Access: http://www.sciencedirect.com/science/article/pii/S258900422030122X

Summary: Polyketides produced by modular polyketide synthases (PKSs) are important small molecules widely used as drugs, pesticides, and biological probes. Tagging these polyketides with a clickable functionality enables the visualization, diversification, and mode of action study through bio-orthogonal chemistry. We report the de novo biosynthesis of alkyne-tagged polyketides by modular type I PKSs through starter unit engineering. Specifically, we use JamABC, a terminal alkyne biosynthetic machinery from the jamaicamide B biosynthetic pathway, in combination with representative modular PKSs. We demonstrate that JamABC works as a trans loading system for engineered type I PKSs to produce alkyne-tagged polyketides. In addition, the production efficiency can be improved by enhancing the interactions between the carrier protein (JamC) and PKSs using docking domains and site-directed mutagenesis of JamC. This work thus provides engineering guidelines and strategies that are applicable to additional modular type I PKSs to produce targeted alkyne-tagged metabolites for chemical and biological applications. : Chemical Engineering; Biochemical Engineering; Metabolic Engineering; Biotechnology Subject Areas: Chemical Engineering, Biochemical Engineering, Metabolic Engineering, Biotechnology