1Department of Chemistry, University of Wisconsin-Madison2Department of Chemistry, University of Virginia

3National Institutes of Health4Thermo Electron, San Jose CA

Sequential ion/ion reactions for large peptide and whole protein

characterization

Joshua J. Coon,1 An Chi,2 Beatrix Ueberheide,2 Jeffrey Shabanowitz,2 Melanie J. Schroeder,2 Lewis Y. Geer,3 Dina

Bai,2 Donald F. Hunt,2and John E. P. Syka4

B

ESIESIe-

multiply-protonatedpeptides

+

++ +

+

+

-

+ - - -

-

+

--

+