A Fine Balancing Act of Type III Polyketide Synthase Review Article

In this issue of Chemistry & Biology, a novel Aldol-Switch mechanism is proposed for the biosynthesis of type III polyketides, which include many antioxidants found in colorful fruits . Based on structural and mutagenesis studies, the Aldol-Switch mechanism suggests that electronic effects balance between two competing cyclization specificities in Type III polyketide synthases. A novel hypothesis is also used to explain stilbenecarboxylate biosynthesis.