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Characterization of intermolecular ?-sheet peptides by mass spectrometry and hydrogen isotope exchange

2000; Wiley; Volume: 14; Issue: 13 Linguagem: Inglês

10.1002/1097-0231(20000715)14

1097-0231

Mario Kraus, Katharina Janek, Michael Bienert, E. H. Krause,

Advanced Proteomics Techniques and Applications

The self-assembly of β-sheet peptide domains resulting in the formation of fibrillar aggregates (amyloids) is a feature of various neurodegenerative disorders. In order to evaluate mass spectrometric methods for the characterization of intermolecular β-sheet structures the hydrogen/deuterium exchange behaviour of model peptides DPKGDPKG-(VT)n-GKGDPKPD-amide (n = 3,4,5,6,7,8), (VT)n-peptides, composed of a central β-sheet-forming domain and N- and C-terminal nonstructured octapeptide sequences, was measured by electrospray ionization mass spectrometry (ESI-MS) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The kinetic analysis of the hydrogen/deuterium exchange (HX) shows that intermolecular β-sheet structures contain slowly exchanging protons (k ≤0.001 1/min). Localization of β-sheet domains was achieved by monitoring the hydrogen exchange of peptide fragments generated via collision-induced dissociation (CID) or post source decay (PSD). The hydrogen exchange kinetics and the β-sheet domains determined by ESI- and MALDI-MS were found to correlate with the length and stability of the β-structure domain of the (VT)n-peptides. Copyright © 2000 John Wiley & Sons, Ltd.