1. Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, USA
2. Computer, Computational, and Statistical Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
3. Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California 94143, USA
4. Department of Chemistry, University of California, Irvine, Irvine, California 92697, USA