1. Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
2. Department
of Biochemistry, University of São Paulo, São Paulo 05508-070, Brazil
3. Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128, United States
4. Department
of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210-1340, United States