1. Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
2. Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, CA 92121, USA.
3. The Pennsylvania State University, University Park, PA 16803, USA.
4. University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.