1. Department of Chemistry, University of South Florida, 4202 East Fowler Avenue, CHE205, Tampa, Florida 33620-5250, United States
2. Laboratory of Computational Biology, National Institutes of Health, National Heart, Lung and Blood Institute, 12 South Drive Rm 3053, Bethesda, Maryland 20892-5690, United States
3. Faculty of Chemistry, Department of Computational Biological Chemistry, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria