Dissociation Behavior of Tryptic and Intramolecular Disulfide-linked Peptide Ions Modified in the Gas Phase via Ion/Ion Reactions.

ABSTRACT: Protonated tryptic peptides, somatostatin-14, and oxytocin have been subjected to reactions with doubly deprotonated 4-formyl-1,3-benzenedisulfonic acid (FBDSA) in the gas phase. The major product is a negatively-charged complex comprised of the peptide and the reagent. Upon dehydration of the complex, all peptides show evidence for Schiff base formation involving a primary amine of the peptide. Some peptides also show evidence for the formation of a relatively strong electrostatic interaction without Schiff base formation (i.e., a mixture of isomeric precursor ions is generated upon dehydration of the complex). Ion trap collision-induced dissociation of the dehydration products from all peptides examined gave distinct product ion spectra relative to the deprotonated and protonated forms o

SUBMITTER: Stutzman JR 

PROVIDER: S-EPMC3297198 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature