1. Laboratoire International Associé Centre National de la Recherche Scientifique et University of Illinois at Urbana−Champaign, Unité Mixte de Recherche n°7019, Université de Lorraine, B.P. 70239, Vandœuvre-lès-Nancy cedex 54506, France
2. School of Physics, Georgia Institute of Technology, 837 State Street, Atlanta, Georgia 30332, United States
3. Theoretical and Computational Biophysics Group, NIH Center for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, 405 N. Mathews Avenue, Urbana, Illinois 61801, United States
4. Department of Biochemistry, University of Illinois at Urbana−Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
5. Department of Biochemistry and Molecular Biology, The University of Chicago, 929 E. 57th Street W225, Chicago, Illinois 60637, United States
6. Department of Chemistry, The University of Chicago, 5735 S. Ellis Avenue, Chicago, Illinois 60637, United States
7. Department of Chemistry, The University of Hawai‘i at Ma̅noa, 2545 McCarthy Mall, Honolulu, Hawaii 96822, United States