title: Quantum Chemical Mass Spectrometry: Verification and Extension of the Mobile Proton Model for Histidine.
abstract: The quantum chemical mass spectrometry for materials science (QCMS2) method is used to verify the proposed mechanism for proton transfer - the Mobile Proton Model (MPM) - by histidine for ten XHS tripeptides, based on quantum chemical calculations at the DFT/B3LYP/6-311+G* level of theory. The fragmentations of the different intermediate structures in the MPM mechanism are studied within the QCMS2framework, and the energetics of the proposed mechanism itself and those of the fragmentations of the intermediate structures are compared, leading to the computational confirmation of the MPM. In addition, the calculations suggest that the mechanism should be extended from considering only the formation of five-membered ring intermediates to include larger-ring intermediates. Graphical Abstract ᅟ.
authors.affiliation: Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020, Antwerp, Belgium.
authors.forename: Julie
authors.initials: J
authors.lastname: Cautereels
authors.affiliation: Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020, Antwerp, Belgium. frank.blockhuys@uantwerpen.be.
authors.forename: Frank
authors.identifier: 0000-0002-2201-6682
authors.initials: F
authors.lastname: Blockhuys
keywords: Density functional theory; Mobile proton model; Quantum chemical mass spectrometry (QCMS2); Tripeptides