Polymerization-Induced Functional Switching of Engineered Polyhydroxyalkanoate Synthase Directs Block Copolymerization

's conformational change, as revealed by cryo-electron microscopy. During the synthesis of the second segment, 2HB-CoA was found to inhibit 3HB-CoA polymerization, enabling the synthesis of the P(2HB) homopolymer segment in the presence of 3HB-CoA. Overall, the results demonstrated the novel sequence-regulating mechanism based on the polymerization-induced functional enhancement. The findings would be useful to further expand the structural variety of PHA for a wider range of applications.