Radical-induced Loss and Rearrangement Reactions in Electron-Capture Dissociation Studied Using a Database Containing Over 15,000 Mass Spectra

摘要

The mechanism of electron-capture dissociation (ECD) involves conversion of even-electron polypeptide n+ ions into radical (n-1)+ ions, with subsequent radical-initiated bond cleavage. One of the two complementary fragments formed in ECD is by necessity a radical. This radical fragment can undergo further rearrangement and dissociation reactions, with radical products continuing to react. O'Connor was first to stress the importance of this radical cascade in ECD [1]. Here we report on a systematic study of the rearrangement and dissociation reactions in ECD performed using a large database of ECD mass spectra.