Protein-ligand binding free energy calculation by the Smooth Reaction Path Generation (SRPG) Method

Area of Science:

• Computational chemistry
• Molecular modeling

Background:

• Accurate calculation of protein-ligand binding free energy is crucial for drug discovery.
• Existing methods often face challenges with computational cost and accuracy in explicit solvent models.

Purpose of the Study:

• To develop a novel and efficient molecular dynamics simulation method for calculating protein-ligand binding free energy.
• To validate the method's performance on both small model systems and complex biological targets.

Main Methods:

• A three-step molecular dynamics simulation approach was developed.
• This involved generating a compound dissociation path, calculating the free energy surface along this path, and analyzing the free energy minimum around the complex.
• The method utilizes an explicit water model for realistic simulations.

Main Results:

• The novel simulation method was successfully applied to a model system (18-crown-6 ether with its ligand ion).
• The method also accurately calculated binding free energies for a realistic system involving a target protein and its inhibitor.
• Successful protein-inhibitor dissociation was achieved, demonstrating the method's efficacy.

Conclusions:

• The developed molecular dynamics simulation method provides a reliable approach for protein-ligand binding free energy calculation.
• This method offers a promising tool for advancing drug discovery and molecular design through accurate binding energy estimations.