1. Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
2. Department
of Biomedical Engineering, Washington University in St. Louis, One Brookings
Drive, Campus Box 1097, St. Louis, Missouri 63130-4899, United States
3. Graduate
Program in Biochemistry and Structural Biology and Graduate Program
in Biophysics, Stony Brook University, Stony Brook, New York 11794, United States