Conformation-specific spectroscopy and photodissociation of cold, protonated tyrosine and phenylalanine.

Détails

ID Serval
serval:BIB_7183D52C78C2
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Conformation-specific spectroscopy and photodissociation of cold, protonated tyrosine and phenylalanine.
Périodique
Journal of the American Chemical Society
Auteur⸱e⸱s
Stearns J.A., Mercier S., Seaiby C., Guidi M., Boyarkin O.V., Rizzo T.R.
ISSN
0002-7863 (Print)
ISSN-L
0002-7863
Statut éditorial
Publié
Date de publication
26/09/2007
Peer-reviewed
Oui
Volume
129
Numéro
38
Pages
11814-11820
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Résumé
We present here ultraviolet and infrared spectra of protonated aromatic amino acids in a cold, 22-pole ion trap. Ultraviolet photofragmentation spectra of protonated tyrosine and phenylalanine show vibronically resolved bands corresponding to different stable conformers: two for PheH+ and four in the case of TyrH+. We subsequently use the resolved UV spectra to perform conformer-specific infrared depletion spectroscopy. Comparison of the measured infrared spectra to density functional theory calculations helps assign the geometry of the various conformers, all of which exhibit NH...pi hydrogen bonds and NH...O=C interactions, with the COOH group oriented either anti or gauche to the aromatic ring. In both molecules the majority of the observed fragments result from dissociation on an excited electronic state. In TyrH+, different conformers excited with practically the same energy exhibit different fragmentation patterns, suggesting that the excited-state dynamics depend upon conformation.
Mots-clé
Algorithms, Cold Temperature, Mass Spectrometry/methods, Molecular Conformation, Phenylalanine/chemistry, Phenylalanine/metabolism, Photochemistry, Protons, Spectrophotometry, Infrared/methods, Tyrosine/chemistry, Tyrosine/metabolism, Ultraviolet Rays
Pubmed
Web of science
Création de la notice
19/06/2019 15:45
Dernière modification de la notice
20/08/2019 15:29
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