Hydrophilicity of cavities in proteins.
Water molecules inside cavities in proteins constitute integral parts of the structure. We have sought a quantitative measure of the hydrophilicity of the cavities by calculating energies and free energies of introducing a water molecule into these cavities. A threshold value of the water-protein interaction energy at -12 kcal/mol was found to be able to distinguish hydrated from empty cavities. It follows that buried waters have entropy comparable to that of liquid water or ice. A simple consistent picture of the energetics of the buried waters provided by this study enabled us to address the reliability of buried waters assigned in experiments.
Zhang
L
L
Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill 27599-7260, USA.
Hermans
J
J
D006860:Hydrogen Bonding; D011487:Protein Conformation; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
D014867:Water