1. Department of Chemistry and Biochemistry, Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, Montana 59803, United States
2. Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003, United States
3. CWRU Center for Synchrotron Biosciences, NSLS-II, Brookhaven National Laboratory, Upton, New York 11973, United States
4. School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
5. Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States