Binding affinity of hydroxamate inhibitors of matrix metalloproteinase-2.

Here we report molecular dynamics (MD) and free energy perturbation (FEP) simulations applied to hydroxamate-matrix metalloproteinase-2 (MMP-2) complex systems. We have developed some new force field parameters for the hydroxamate functional group that were not included in the AMBER94 force field but were necessary in our simulations. For the representation of the active zinc center, a bonded model was adopted in which restrained electrostatic potential fitting (RESP) charges were used as the electrostatic representation of this model. Using the resulted bonded model, FEP simulations predict the relative binding free energy in good agreement with the experimental value. By analyzing the molecular dynamics (MD) trajectories of the two complex systems, we can provide an explanation of why one of the two inhibitors is favored over the other. The results provide a chemical insight into the interactions between inhibitor and enzyme, and can indicate changes in the inhibitor that would enhance inhibitor-enzyme interactions.