Predicting protein-ligand binding affinity and correcting crystal structures with quantum mechanical calculations:...

Area of Science:

• Computational chemistry
• Structural biology
• Biophysics

Background:

• Accurate computation of host-guest and protein-ligand interactions is crucial for understanding biological processes.
• Quantum mechanics offers high accuracy but is computationally expensive.
• Existing methods often lack the precision needed for detailed interaction analysis.

Purpose of the Study:

• To develop a computationally efficient yet accurate method for calculating binding energies.
• To improve the agreement between computed and experimentally measured binding energies.
• To enable quantitative predictions of molecular interactions and structural properties.

Main Methods:

• Employing quantum mechanics focused on receptor atoms near the ligand.
• Integrating computed ligand log P values into the calculations.
• Applying the method to lactate dehydrogenase A (LDH-A).

Main Results:

• Significant improvement in agreement between computed and measured binding energies.
• Accurate prediction of conformational, tautomeric, and protonation states.
• Identification of potential errors in Protein Data Bank structures for LDH-A.
• Demonstrated ability to propose more chemically realistic structures.

Conclusions:

• The developed computational approach enhances the accuracy of binding energy predictions.
• This method provides a powerful tool for analyzing protein-ligand interactions and validating structural data.
• It facilitates the proposal of more chemically accurate protein structures, improving structural biology research.