Probing the fragmentation reactions of protonated glycine oligomers via multistage mass spectrometry and gas phase ion molecule hydrogen/deuterium exchange

Abstract

An ion trap mass spectrometer equipped with electrospray ionization has been modified to study the structure of protonated polyglycyl peptides Gn (where n = 2-5 glycine residues) and their product ions formed by collision induced dissociation tandem mass spectrometry (CID MS/MS) via the novel application of gas phase ion-molecule hydrogen/deuterium (H/D) exchange reactions. In particular, the structures of the b2, b3, b4, and b5 ions formed via CID MS/MS from various protonated glycine oligomer precursors have been examined. The b2 ions, formed from the protonated G2 and G3 precursor ions, the b3 ion from the protonated G3 precursor, and the b4 ion from the protonated G5 ion all undergo CID ..