Sequence-ion studies in peptides: the generation of C" ions.
The mechanism for the formation of C"-type ions from protonated peptides, produced under conditions of fast-atom bombardment and collisional activation was investigated. Comparison of the tandem mass spectra of the [M + H]+ ions of a model peptide and the corresponding [Md + D]+ ions, in which all exchangeable hydrogens are replaced with deuterium, revealed that neither the carboxylic hydrogen nor a hydrogen from a nitrogen atom is involved in the process of migration of a hydrogen which leads to the formation of C"n-type ions. The most feasible position from which the transferred hydrogen originates is that at the first C-atom in the side-chain of the adjacent amino acid.
van Dongen
W D
WD
University of Utrecht, Faculty of Chemistry, Bijvoet Center for Biomolecular Research, The Netherlands.
de Koster
C G
CG
Heerma
W
W
Haverkamp
J
J
D000595:Amino Acid Sequence; D003903:Deuterium; D006859:Hydrogen; D007477:Ions; D013058:Mass Spectrometry / Q000379:methods; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment
D007477:Ions; D009842:Oligopeptides; D010455:Peptides; C080939:glycyl-glycyl-valine; D006859:Hydrogen; D003903:Deuterium