HYDROPHOBIC-HYDROPHILIC FORCES IN PROTEIN-FOLDING

The total force exerted on each atom, or group of atoms, of a protein can be split into two parts: A direct force originating from the protein itself and an indirect pact, induced by the solvent. We focus on the solvent induced part of the force exerted on a typical hydrophobic (say methyl) and hydrophilic (say hydroxyl) groups. It is argued that the solvent induced force between hydrophilic groups are stronger than the corresponding forces between hydrophobic groups. Some recent simulations of the indirect force confirm this conclusion. The implication of these findings to biochemical processes is discussed.