1. Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Canada
2. Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, T6G 2J7, Canada
3. Departments of Chemistry and Biomedical Engineering, Michigan State University, East Lansing, Michigan 48824, United States
4. Department of Chemistry, The University of British Columbia, Kelowna, V1V 1V7, Canada
5. Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan