1. Department of Chemistry and Biochemistry, Molecular Biology Institute, and University of California at Los Angeles−U.S. Department of Energy Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, California 90095-1570, Department of Life Science, POSTECH, Pohang, Kyungbuk 790-784, Korea, Division of Molecular Structure and Function, Research Institute, Hospital for Sick Children, Toronto M5G 1X8, Ontario, Canada, and Department of...