1. Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
2. Skaggs School of Pharmacy and Pharmaceutical Sciences, and San Diego Supercomputer Center, University of California, San Diego, La Jolla, CA 92093, USA.
3. Pfizer Worldwide Research and Development, 10770 Science Center Drive, San Diego, CA 92121, USA.