Covalent and non-covalent binding in the ion/ion charge inversion of peptide cations with benzene-disulfonic acid anions.

ABSTRACT: Protonated angiotensin II and protonated leucine enkephalin-based peptides, which included YGGFL, YGGFLF, YGGFLH, YGGFLK and YGGFLR, were subjected to ion/ion reactions with the doubly deprotonated reagents 4-formyl-1,3-benzenedisulfonic acid (FBDSA) and 1,3-benzenedisulfonic acid (BDSA). The major product of the ion/ion reaction is a negatively charged complex of the peptide and reagent. Following dehydration of [M + FBDSA-H](-) via collisional-induced dissociation (CID), angiotensin II (DRVYIHPF) showed evidence for two product populations, one in which a covalent modification has taken place and one in which an electrostatic modification has occurred (i.e. no covalent bond formation). A series of studies with model systems confirmed that strong non-covalent binding of the FBDSA reagent

SUBMITTER: Stutzman JR 

PROVIDER: S-EPMC3435877 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature