1. Department of Chemistry, Bogazici University, Bebek, Istanbul 34342, Turkey
2. Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, United States
3. Biochemical and Biophysical Systems Group, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
4. Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States