1. Department of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
2. Human Proteomics Program, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
3. Department of Biochemistry, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
4. Department of Cell and Regenerative Biology, University of Wisconsin—Madison, 1111 Highland Avenue, WIMR II 8551, Madison, Wisconsin 53705, United States