1. Boothroyd Scientific Consulting Ltd., 71-75 Shelton Street, London WC2H 9JQ, Greater London, U.K.
2. Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80309, United States
3. Department of Chemistry, University of California, Irvine, California 92617, United States
4. Department of Pharmaceutical Sciences, University of California, Irvine, California 92617, United States
5. Department of Chemistry, University of California, Davis, California 95616, United States
6. Computational & Systems Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States