Computational Insight Into Vitamin K1 ?-Hydroxylation by Cytochrome P450 4F2.

ABSTRACT: Vitamin K1 (VK1) plays an important role in the modulation of bleeding disorders. It has been reported that ?-hydroxylation on the VK1 aliphatic chain is catalyzed by cytochrome P450 4F2 (CYP4F2), an enzyme responsible for the metabolism of eicosanoids. However, the mechanism of VK1 ?-hydroxylation by CYP4F2 has not been disclosed. In this study, we employed a combination of quantum mechanism (QM) calculations, homology modeling, molecular docking, molecular dynamics (MD) simulations, and combined quantum mechanism/molecular mechanism (QM/MM) calculations to investigate the metabolism profile of VK1 ?-hydroxylation. QM calculations based on the truncated VK1 model show that the energy barrier for ?-hydroxylation is about 6-25 kJ/mol higher than those at other potential sites of metabolism. However, results from the MD simulations indicate that hydroxylation at the ?-site is more favorable than at the other potential sites, which is in accordance with the experimental observation. The evaluation of MD simulations was further endorsed by the QM/MM calculation results. Our studies thus suggest that the active site residues of CYP4F2 play a determinant role in the ?-hydroxylation. Our results provide structural insights into the mechanism of VK1 ?-hydroxylation by CYP4F2 at the atomistic level and are helpful not only for characterizing the CYP4F2 functions but also for looking into the ?-hydroxylation mediated by other CYP4 enzymes.

SUBMITTER: Li J 

PROVIDER: S-EPMC6167488 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature