Electron transfer dissociation of peptide anions

  • Joshua J. Coon
  • Jeffrey Shabanowitz
  • Donald F. Hunt
  • John E. P. Syka
Short Communication


Ion/ion reactions of multiply deprotonated peptide anions with xenon radical cations result in electron abstraction to generate charge-reduced peptide anions containing a free-radical site. Peptide backbone cleavage then occurs by hydrogen radical abstraction from a backbone amide N to facilitate cleavage of the adjacent C-C bond, thereby producing a- and x-type product ions. Introduction of free-radical sites to multiply charged peptides allows access to new fragmentation pathways that are otherwise too costly (e. g., lowers activation energies). Further, ion/ion chemistry, namely electron transfer reactions, presents a rapid and efficient means of generating odd-electron multiply charged peptides; these reactions can be used for studying gas-phase chemistries and for peptide sequence analysis.


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Copyright information

© American Society for Mass Spectrometry 2005

Authors and Affiliations

  • Joshua J. Coon
    • 1
  • Jeffrey Shabanowitz
    • 1
  • Donald F. Hunt
    • 1
    • 4
  • John E. P. Syka
    • 2
    • 3
  1. 1.Department of ChemistryUniversity of VirginiaCharlottesvilleUSA
  2. 2.Engineering Physics ProgramUniversity of VirginiaCharlottesvilleUSA
  3. 3.Thermo ElectronSan Jose
  4. 4.the Department of Pathology, Health Sciences CenterUniversity of VirginiaCharlottesville

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