Inhibiting mechanism of small molecule toward the p53-MDM2 interaction: A molecular dynamic exploration

Disruption of the p53-MDM2 interaction has been an efficient strategy to renew the function of wild-type p53. In this work, molecular dynamic simulations, molecular mechanics-generalized Born surface area method, and principal component analysis were combined to probe interaction mechanism of inhibitors 2TZ, 2U0, 2U1, 2U5, 2U6, and 2U7 with MDM2. The rank of our current predicted binding free energies is in agreement with that of the experimental values. The results demonstrate that the introductions of thiazole and pyridine rings into 2TZ as well as the change in the orientation of inhibitors lead to the increase in the polar interactions of 2U0, 2U1, 2U5, 2U6, and 2U7 with MDM2 relative to 2TZ. The information derived from principal component analysis suggests that inhibitor bindings produce significant effect on the binding cleft of MDM2 and make the binding cleft wider and bigger so as to accommodate different type inhibitors. This study is looked forward to contributing theoretical hints for designs of potent inhibitors targeting the p53-MDM2 interaction.