Gas-phase bioconjugation of peptides via ion/ion charge inversion: Schiff base formation on the conversion of cations to anions.

ABSTRACT: The selective covalent modification of singly protonated peptides in the gas-phase via ion/ion charge inversion reactions is demonstrated. Doubly deprotonated 4-formyl-1,3-benzene disulfonic acid serves as a reagent anion for forming a Schiff base via the reaction of a primary amine on the peptide and the aldehyde functionality of the reagent anion. The process is initiated by the formation of an ion/ion complex comprised of the two reactants. Ion trap collisional activation of the complex results in loss of water from the intermediate that gives rise to Schiff base formation. N-terminally acetylated peptides with no lysine residues do not undergo covalent bond formation upon reaction with the reagent anion. Rather, the adduct species simply loses the reagent either as a neutral species or

SUBMITTER: Hassell KM 

PROVIDER: S-EPMC2834292 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature