Comparing a simple theoretical model for protein folding with all-atom molecular dynamics simulations.

Area of Science:

• Computational biology
• Biophysics
• Theoretical chemistry

Background:

• Advances in computing allow for microsecond all-atom molecular dynamics (MD) simulations of protein folding.
• These simulations offer a powerful tool to test theoretical models of protein folding dynamics.

Purpose of the Study:

• To compare microsecond all-atom MD simulations with theoretical models of protein folding.
• To test a key assumption of an Ising-like theoretical model regarding native structure formation during protein folding.

Main Methods:

• Utilized microsecond all-atom molecular dynamics trajectories from recent simulations.
• Simulated the master equation of a native-centric Ising-like model for the villin subdomain.
• Employed two adjustable thermodynamic parameters and one temperature-dependent kinetic parameter for model simulation.

Main Results:

• MD simulations are consistent with the Ising-like model's assumption that native structure grows in limited regions of the amino acid sequence.
• The distribution of folding mechanisms predicted by the native-centric model closely matches the distribution observed in MD trajectories.
• The model accurately reproduces simulation data using only two thermodynamic and one kinetic parameter.

Conclusions:

• The study validates a key assumption of the Ising-like theoretical model for protein folding.
• Computational simulations and theoretical models show remarkable agreement in predicting protein folding mechanisms.
• This work supports a "native-centric" view of protein folding, where specific sequence regions drive structure formation.