کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5559515 | 1403288 | 2016 | 6 صفحه PDF | دانلود رایگان |
- CocE-(+)-cocaine binding mode is similar to the CocE-(â)-cocaine binding mode.
- A significant free energy barrier exists in the CocE-(+)-cocaine binding process.
- No free energy barrier exists in the CocE-(â)-cocaine binding process.
- (+)-Cocaine and (â)-cocaine have very close binding free energies with CocE.
The combined molecular dynamics (MD) and potential of mean force (PMF) simulations have been performed to determine the free energy profile of the CocE)-(+)-cocaine binding process in comparison with that of the corresponding CocE-(â)-cocaine binding process. According to the MD simulations, the equilibrium CocE-(+)-cocaine binding mode is similar to the CocE-(â)-cocaine binding mode. However, based on the simulated free energy profiles, a significant free energy barrier (â¼5Â kcal/mol) exists in the CocE-(+)-cocaine binding process whereas no obvious free energy barrier exists in the CocE-(â)-cocaine binding process, although the free energy barrier of â¼5Â kcal/mol is not high enough to really slow down the CocE-(+)-cocaine binding process. In addition, the obtained free energy profiles also demonstrate that (+)-cocaine and (â)-cocaine have very close binding free energies with CocE, with a negligible difference (â¼0.2Â kcal/mol), which is qualitatively consistent with the nearly same experimental KM values of the CocE enzyme for (+)-cocaine and (â)-cocaine. The consistency between the computational results and available experimental data suggests that the mechanistic insights obtained from this study are reasonable.
Journal: Chemico-Biological Interactions - Volume 259, Part B, 25 November 2016, Pages 142-147