306 / 2019-01-15 11:22:00

Ab Inition Dynamics Simulation of the Potassium Channel Protein Ligand Studied with Two-dimensional Infrared Spectra

Electric Field,,coupled vibration,rotation isomerization

全体主题 > Fundamental Physics at Extremes

Two-dimensional infrared (2D-IR) spectra has been proven to be an extremely useful method to study the coupling between chemical bonds and rotational isomerization under thermal equilibria. Here, we present simulated results on the dynamics of the potassium channel protein’s ligand for different electric field focusing on the potential energy distribution and conformational transformation, where the DFT/B3LYP method is applied. We have utilized the vibration energy distribution analysis (VEDA) to successfully resolve anharmonic vibration frequency of chemical bonds. It is found that the anharmonic vibration frequency and anharmonicity of C-H bond and phosphate group are affected by electric field. The asymmetric and symmetric stretching vibrations of C-H bond are no longer coupled when electric field are -2×10-3 a.u. and -1×10-3 a.u. The most important is that the ligand cannot undergo rotational isomerization when electric field is -3×10-3 a.u., which indicates that electric field has no negligible influence on the potassium channel protein function. More importantly, our study will provide reference and guidance for the following experiments and calculations about the 2D-IR spectra of the potassium channels’ ligand in mid-infrared region.