Shattering of Peptide Ions on Self-Assembled Monolayer Surfaces.

Journal Article · Wed Feb 12 04:00:00 EST 2003 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/ja027915t· OSTI ID:15005809

Laskin, Julia; Bailey, Thomas; Futrell, Jean H

Time- and energy-resolved surface-induced dissociation (SID) of des-Arg1- and des-Arg9-bradykinin on a fluorinated self-assembled monolayer (SAM) surface was studied using a novel Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially equipped to perform SID experiments. Time-resolved data was modeled using an RRKM-based approach developed in our laboratory. Both experimental observations and modeling establish a very sharp transition in the dynamics of ion-surface interaction: the shattering transition. Shattering opens a variety of dissociation pathways that are not accessible to slow collisional and thermal ion activation. This results in a much better sequence coverage for the singly protonated peptides than dissociation patterns obtained with any of the slow activation methods. Modeling demonstrated that for short reaction delays dissociation of these peptides is solely determined by shattering. Internal energies required for shattering transition are approximately the same for des-Arg1 and des-Arg9-bradykinin, resulting in the overlap of fragmentation efficiency curves obtained at short reaction delays. At longer delay times parent ions depletion is mainly determined by a slow decay rate and fragmentation efficiency curves for des-Arg1 and des-Arg9-bradykinin diverge. Dissociation thresholds of 1.17 and 1.09 eV and activation entropies of -22.2 and -23.3 cal/mol K were obtained for des-Arg1 and des-Arg9-bradykinin from RRKM modeling of time-resolved data. Dissociation parameters for des-Arg1-bradykinin are in good agreement with parameters derived from thermal experiments. However, there is a significant discrepancy between the thermal data and dissociation parameters for des-Arg9-bradykinin obtained in this study. The difference is attributed to the differences in conformations that undergo thermal activation and activation by ion-surface collisions prior to dissociation.

• Research Organization: Pacific Northwest National Lab., Richland, WA (US), Environmental Molecular Sciences Laboratory (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 15005809
• Report Number(s): PNNL-SA-37950; 6291
• Journal Information: Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 6 Vol. 125; ISSN JACSAT; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
59 BASIC BIOLOGICAL SCIENCES
DISSOCIATION
ENVIRONMENTAL MOLECULAR SCIENCES LABORATORY
NULL
FRAGMENTATION
ION CYCLOTRON-RESONANCE
MASS SPECTROMETERS
PEPTIDES
SIMULATION