1. Department of Biochemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
2. Center for Biophysics and Quantitative Biology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
3. Structural Biology & Biophysics Facility, University of Rochester Medical Center, Rochester, New York 14642, United States
4. Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
5. Beckman Institute for Advanced Science & Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States
6. Department of Pathology & Laboratory Medicine, University of Rochester Medical Center, Rochester, New York 14642, United States