Protein dynamics in solution and in a crystalline environment: a molecular dynamics study.

Area of Science:

• Biophysics
• Computational Biology
• Protein Dynamics

Background:

• Understanding protein behavior requires considering their environment.
• Solvent and crystalline environments significantly influence protein structure and dynamics.

Purpose of the Study:

• To investigate the effects of solvent and crystalline environments on protein dynamics.
• To compare protein behavior in vacuo, solution, and crystal using molecular dynamics simulations.

Main Methods:

• Three 25-picosecond molecular dynamics simulations of bovine pancreatic trypsin inhibitor (BPTI) at 300 K.
• Simulations included BPTI in vacuum, with solvent, and surrounded by crystal image atoms.

Main Results:

• Protein dynamics in solution and crystal are similar to vacuum simulations.
• Solvent and crystal environments yield equilibrium structures closer to X-ray data.
• Solvent alters surface residue dynamics and long side chain movements, while the crystal environment fixes specific side chains.

Conclusions:

• Environmental effects on protein dynamics are largely similar across vacuum, solution, and crystal.
• Realistic environments enhance structural accuracy and density predictions.
• Solution environment effects can potentially be modeled using mean field and stochastic dynamics.