Affiliation:
1. Key Laboratory of Tropical Marine Bioresources and Ecology Guangdong Key Laboratory of Marine Materia Medica South China Sea Institute of Oceanology Chinese Academy of Science Guangzhou 510301 China
2. University of Chinese Academy of Science 19 Yuquan Road Beijing 100049 China
3. Sanya Institute of Oceanology Eco-Environmental Engineering Yazhou Scientific Bay Sanya 572000 China
Abstract
AbstractRegio‐ and chemoselective C−H activation at multi‐positions of a single molecule is fascinating but chemically challenging. The homologous cytochrome P450 enzymes IkaD and CftA catalyze multiple C−H oxidations on the same polycyclic tetramate macrolactam (PoTeM) ikarugamycin, with distinct regio‐ and chemoselectivity. Herein we provide mechanistic understanding of their functional differences by solving crystal structures of IkaD and CftA in complex with ikarugamycin and unnatural substrates. Distinct conformations of the F/G region in IkaD and CftA are found to differentiate the orientation of PoTeM substrates, by causing different binding patterns with polar moieties to determine site selection, oxidation order, and chemoselectivity. Fine‐tuning the polar subpocket altered the regioselectivity of IkaD, indicating that substrate re‐orientation by mutating residues distal to the oxidation site could serve as an important method in future engineering of P450 enzymes.
Funder
National Natural Science Foundation of China