1. Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
2. Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
3. Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
4. Department of Physics, Auburn University, Auburn, Alabama 36849, United States
5. Department of Biochemistry, Center for Biophyics and Quantitative Biology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States