A. Wallqvist et Dg. Covell, COOPERATIVITY OF WATER-SOLUTE INTERACTIONS AT A HYDROPHILIC SURFACE, Journal of physical chemistry, 99(15), 1995, pp. 5705-5712
We have measured the reversible work required to assemble different se
ts of weak model charges at a water/wall interface using molecular dyn
amics methods and free energy perturbation techniques. It is found tha
t water is a strong mediator of like-charge repulsive forces due to th
e ability of water molecules to adopt low free energy configurations t
hat maximize the water-ion interaction while minimizing the penalty of
the concomitant water rearrangement. The cooperativity of this mechan
ism is enhanced at smaller charge separations, but is not associated w
ith any strong preferential hydration structure. The presence of solve
nt-stabilized, like-charge-charge pairs embedded on a surfaces implies
an additional mechanism by which water can stabilize biomolecular ass
emblies.