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Balancing solvation and intramolecular interactions: toward a consistent generalized Born force field
Jianhan Chen1, Wonpil Im, Charles L Brooks
1Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|March 16, 2006
Summary
Optimizing implicit solvent models, like generalized Born (GB), with atomic radii and backbone energetics improves biomolecule simulations. This balanced force field accurately predicts peptide folding and protein dynamics.
Area of Science:
- Computational chemistry
- Biophysics
- Molecular dynamics
Background:
- Implicit solvent models, especially generalized Born (GB) electrostatics, are crucial for studying biomolecules computationally.
- Current GB models face limitations in parametrization, affecting accuracy in biological simulations.
Purpose of the Study:
- To develop a balanced implicit solvent force field by optimizing atomic radii and protein backbone torsional energetics.
- To improve the accurate characterization of solvent effects in theoretical and computational studies of biological systems.
Main Methods:
- Optimized atomic radii and adjusted protein backbone torsional energetics for the implicit solvent force field.
- Utilized potentials of mean force (PMFs) from explicit solvent simulations and conformational equilibria from replica exchange molecular dynamics (REX-MD) simulations for parameter optimization.
- Validated the optimized force field using helical and beta-hairpin peptides, including trpzip2 and Trp-Cage.
Main Results:
- Achieved a balanced implicit solvent force field that better captures the interplay between solvation and intramolecular forces.
- Obtained correct conformational equilibria for various helical and beta-hairpin peptides.
- Demonstrated the force field's robustness by successfully folding benchmark peptide systems.
Conclusions:
- The optimized, physics-based implicit solvent force field offers improved accuracy for biomolecular simulations.
- This balanced force field is highly applicable to diverse biological problems, including protein folding and dynamics.
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