Dr. Bo Li
Department of Mathematics and NSF Center for Theoretical Biological Physics
University of California, San Diego
Friday, November 19, 2010
4:00pm
Rowland Hall, Rm 440R
A novel variational approach to the molecular solvation with a continuum solvent is introduced. In this approach [Dzubiella, Swanson, and McCammon 2006], an effective free-energy functional of all possible solute-solvent interfaces is minimized to determine equilibrium conformations and minimum solvation free energies. The functional consists of volume and surface energies of solutes, solute-solvent dispersive interactions, and electrostatic contributions which is approximated by the Coulomb-field or Yukawa-field. Solute molecular mechanics can be coupled with the variational solvation. A robust level-set method is developed to track numerically such equilibrium solute-solvent interfaces. Special techniques are designed to treat the Gaussian curvature arising from the Tolman correction of surface tension. Extensive numerical results with comparison with molecular dynamics simulations demonstrate the success of this new approach in capturing the hydrophobic interaction and drying-and-wetting fluctuation between multiple equilibrium states. These properties are in general difficult to describe by most of the existing implicit-solvent models in which ad hoc solute-solvent interfaces are pre-defined and different parts of the free energy are decoupled. This is a joint work with Li-Tien Cheng, Zhongming Wang, Yang Xie, Piotr Setny, Jianwei Che, Joachim Dzubiella, and J. Andrew McCammon.