1. Thermo Fisher Scientific, 355 River Oaks Parkway, San Jose, California 95134, United States
2. Thermo Fisher Scientific, 790 Memorial Drive, Suite 2D, Cambridge, Massachusetts 02139, United States
3. Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, 2170 Campus Drive, Evanston, Illinois 60208, United States
4. Department of Biology, University of Oklahoma, 730 Van Vleet Oval, Norman, Oklahoma 73071, United States