"Martinizing" the Variational Implicit Solvent Method (VISM): Solvation Free Energy for Coarse-Grained Proteins

Area of Science:

• Computational chemistry
• Biophysics
• Theoretical biology

Background:

• Solvation is crucial for biomolecular processes like recognition, folding, and function.
• The Variational Implicit Solvent Method (VISM) estimates solvation free energies for complex biomolecules.
• VISM uniquely couples hydrophobic, van der Waals, and electrostatic interactions via a solvation interface functional.

Purpose of the Study:

• To extend VISM to larger-scale applications by integrating it with coarse-grained models.
• To evaluate the performance of the new MARTINI-VISM (MVISM) method against atomistic VISM (AVISM).
• To assess MVISM's utility for studying solvation properties of biomolecular complexes.

Main Methods:

• Combined VISM with coarse-grained solute Hamiltonians from the MARTINI framework.
• Compared MVISM with AVISM for proteins of varying size, shape, and charge.
• Applied MVISM to analyze the solvation of the barnase-barstar encounter complex.

Main Results:

• MVISM successfully applied VISM to larger-scale biomolecular systems.
• Demonstrated MVISM's ability to study solvation properties of biomolecular complexes like barnase-barstar.
• Showed comparable results between MVISM and AVISM for tested proteins.

Conclusions:

• Coarse-graining biomolecules with the MARTINI force field is a valuable approach for VISM.
• MVISM broadens the applicability of VISM and MARTINI for future research.
• This integration facilitates efficient solvation energy calculations for large biomolecular assemblies.