Crucial gating residues govern the enhancement of peroxygenase activity in an engineered cytochrome P450 O -demethylase.
Zhao, P., Jiang, Y., Wang, Q., Chen, J., Yao, F., Cong, Z.(2024) Chem Sci 15: 8062-8070
- PubMed: 38817576 
- DOI: https://doi.org/10.1039/d4sc02418d
- Primary Citation of Related Structures:  
8WS4 - PubMed Abstract: 
P450-catalyzed O -demethylation reactions have recently attracted particular attention because of their potential applications in lignin bioconversion. We recently enabled the peroxygenase activity of CYP199A4, a NADH-dependent cytochrome P450 monooxygenase from Rhodopseudomonas palustris , by engineering a hydrogen peroxide (H 2 O 2 ) tunnel. In this report, we reveal by crystallography and molecule dynamics simulations that key residues located at one of the water tunnels in CYP199A4 play a crucial gating role, which enhances the peroxygenase activity by regulating the inflow of H 2 O 2 . These results provide a more complete understanding of the mechanism by which monooxygenase is converted into peroxygenase activity through the H 2 O 2 tunnel engineering (HTE) strategy. Furthermore, a library of engineered CYP199A4 peroxygenases was constructed to explore their application potentials for O -demethylation of various methoxy-substituted benzoic acid derivatives. The engineered CYP199A4 peroxygenases showed good functional group tolerance and preferential O -demethylation at the meta - or para -position, indicating potential O -demethylation of H- and G-type lignin monomers. This work reveals the feasibility of the HTE strategy in creating P450 peroxygenase from a mechanistic perspective, laying the foundation for developing an effective P450 O -demethylase applicable in lignin bioconversion.
Organizational Affiliation: 
CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Synthetic Biology Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences Qingdao Shandong P. R. China congzq@qibebt.ac.cn.