Fragmentation of protonated peptides: surface-induced dissociation in conjunction with a quantum mechanical approach.
This paper describes the results of a systematic investigation designed to assess the utility of surface-induced dissociation in the structural analysis of small peptides (500-1800u). A number of different peptides, ranging in mass and amino acid sequence, are fragmented by collision with a surface in a tandem mass spectrometer and the spectra are compared with data obtained by gas-phase collisional activation. The surface-induced dissociation spectra provide ample sequence information for the peptides. Side-chain cleavage ions of type w, which are generally detected upon kiloelectronvolt collisions with gaseous targets but not upon electronvolt collisions with gaseous targets, are detected in the ion-surface collision experiments. A theoretical approach based on MNDO bond order calculations is suggested for the description of peptide fragmentation. This model, supplemented by ab initio calculations, serves as a complement to the experimental work described in the paper and explains (i) the easy cleavage of the amide bond, (ii) charge-remote backbone and side-chain cleavages, and (iii) the influence of intramolecular H-bonding.
McCormack
A L
AL
Department of Chemistry, Virginia Commonwealth University, Richmond 23284-2006.
Somogyi
A
A
Dongré
A R
AR
Wysocki
V H
VH
D000595:Amino Acid Sequence; D006860:Hydrogen Bonding; D007477:Ions; D013058:Mass Spectrometry / Q000379:methods; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D011522:Protons; D013499:Surface Properties
D007477:Ions; D010446:Peptide Fragments; D010455:Peptides; D011522:Protons