Polyketides are a structurally complex class of natural products with therapeutic and agrochemical utility. 1 Polyketide backbones are generated by the repetitive decarboxylative condensation of simple malonic acid derivatives by large multifunctional proteins called polyketide synthases (PKSs). These modular enzymes can be genetically modified to biosynthesize new “unnatural” natural products. 2 Notwithstanding the spectacular ...