Engineered Biosynthesis of Complex Disorazol Polyketides in a Streamlined Burkholderia thailandensis .

Engineering the biosynthetic pathways of complex natural products is a significant approach to obtain derivatives with improved properties. Here, we constructed a streamlined engineered biosynthesis system of myxobacterium-derived complex polyketide disorazol in a heterologous host, E264. Inactivation of dehydratase domains in the disorazol biosynthetic pathway led to the production of two hydroxylated derivatives. Module deletion allowed the generation of an unnatural derivative with a truncated macrolactone ring, and the ACP-KS linker was the optimal fusion region for module deletion in this -AT polyketide synthase. These disorazol derivatives showed different activities against human cancer cell lines ranging from the nanomolar to micromolar level, suggesting the primary structure-activity relationship. The PKS engineering enables structural derivatization of disorazol, facilitating the in-depth engineered biosynthesis of polyketides.