Infrared Photoactivation Reduces Peptide Folding and Hydrogen-Atom Migration following ETD Tandem Mass Spectrometry

摘要

Electron capture dissociation (ECD)-an experiment generally performed within the high magnetic field of a Fourier transform ion cyclotron resonance mass spectrometer- results from the mutual storage of thermal electrons with multiply protonated peptide cations. The technique is particularly useful, as it generates random backbone cleavage with little regard to the presence of posttranslational modifications (PTMs), amino acid composition, or peptide length. Electron transfer dissociation (ETD), the ion-ion analogue of ECD, is conducted in radio-frequency (RF) quadrupole ion trap devices, in which radical anions serve as electron donors. Since it can be implemented on virtually any mass spectrometer with an RF ion transfer or storage device, ETD has become an increasingly widespread dissociation method.