1. Department of Biochemistry and Molecular Biology, The University of Kansas Medical Center, MS 3030, 3901 Rainbow Boulevard, Kansas City, Kansas 66160
2. School of Molecular and Microbial Biosciences, The University of Sydney, Sydney, NSW 2006, Australia
3. Department of Chemistry, The University of Utah, 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112-0850