Faster protein folding using enhanced conformational sampling of molecular dynamics simulation

Area of Science:

• Computational Chemistry
• Biophysics
• Molecular Dynamics

Background:

• Replica exchange method (REM) is crucial for conformational sampling in molecular simulations.
• Enhancing sampling efficiency in REM is vital for accurate peptide/protein folding studies.

Purpose of the Study:

• To introduce and validate the swarm particle-like molecular dynamics (SPMD) approach.
• To demonstrate SPMD's ability to improve conformational sampling in REM simulations.
• To assess SPMD's efficiency in peptide/protein folding simulations.

Main Methods:

• Developed an augmented dynamical system of equations for SPMD.
• Applied SPMD in conjunction with REM for fully atomistic and coarse-grained models.
• Utilized SPMD for transition path sampling on a 2D surface.
• Implemented protocols using CHARMM software for performance comparison.

Main Results:

• SPMD significantly improved conformational phase space sampling efficiency when combined with REM.
• Achieved folded structures in shorter simulation times compared to standard REM (<0.5 ns for known structures, ~40 ns for blind prediction).
• Root mean square deviations from reference structures were consistently below 2Å.

Conclusions:

• The SPMD approach offers a substantial enhancement over standard REM for molecular dynamics simulations.
• SPMD accelerates peptide/protein folding simulations, enabling faster structure prediction and analysis.
• The method demonstrates improved transition path sampling capabilities.