Proteins in Mixed Solvents: A Molecular-level Perspective
Name
MEBCS021.pdf
Size
1.97 MB
Format
Adobe PDF
Checksum (MD5)
2ba28f73cb179822efdf083cb5229fb7
Author(s) • •
Baynes, Brian M.
Wang, Daniel I.C.
Trout, Bernhardt L.
Date Issued
January 2004
Series/Report no.
Molecular Engineering of Biological and Chemical Systems (MEBCS);
Abstract
We present a statistical mechanical approach for quantifying thermodynamic properties of proteins in mixed solvents. This approach, based on molecular dynamics simulations which incorporate all atom models and the theory of preferential binding, allows us to compute transfer free energies with experimental accuracy and does not incorporate any adjustable parameters. Specifically, we applied our approach to the model proteins RNase A and T1, and the solvent components water, glycerol, and urea. We found that the observed differences in the binding of glycerol and urea to RNase T1 and A are predominantly a consequence of density differences in the first coordination shell of the protein with the cosolvents, but the second solvation shell also contributes to the overall binding coefficients. The success of this approach in modeling preferential binding indicates that it incorporates the important underlying physics of proteins in mixed solvent systems and that the difficulty in quantitative prediction to date can be surmounted by explicitly incorporating the complex protein-solvent and solvent-solvent interactions.
Subjects
glycerol
molecular dynamics
preferential binding
ribonuclease
urea
Persistent DSpace Link