1. Department of Chemistry and Molecular Biology, Center for Metabolomics, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
2. Department of Cell Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
3. Institute for Systems Biology, Seattle, Washington 98103-8904, United States