1. Center for High Performance Simulation and Department of Chemical and Biomolecular Engineering, North Carolina State University at Raleigh, Box 7905, Raleigh, North Carolina 27695-7905, Centre de Recherche en Matière Condensée et Nanosciences, Campus de Luminy, 13288 Marseille, Cedex 09, France, and Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom