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Charge-site-dependent dissociation of hydrogen-rich radical peptide cations upon vacuum UV photoexcitation.

ABSTRACT: Here, 193 nm vacuum ultraviolet photodissociation (VUVPD) was used to investigate the fragmentation of hydrogen-rich radical peptide cations generated by electron transfer reactions. VUVPD offers new insight into the factors that drive radical- and photon-directed processes. The location of a basic Arg site influences photon-activated C(?)-C(O) bond cleavages of singly charged peptide radical cations, an outcome attributed to the initial conformation of the peptide as supported by molecular dynamics simulated annealing and the population of excited states upon UV excitation. This hybrid ETD/VUVPD method was employed to identify phosphorylation sites of the kinase domain of human TRPM7/ChaK1.

SUBMITTER: Madsen JA

PROVIDER: S-EPMC4136645 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Charge-site-dependent dissociation of hydrogen-rich radical peptide cations upon vacuum UV photoexcitation.

Madsen James A JA Cheng Ryan R RR Kaoud Tamer S TS Dalby Kevin N KN Makarov Dmitrii E DE Brodbelt Jennifer S JS

Chemistry (Weinheim an der Bergstrasse, Germany) 20120316 17

Here, 193 nm vacuum ultraviolet photodissociation (VUVPD) was used to investigate the fragmentation of hydrogen-rich radical peptide cations generated by electron transfer reactions. VUVPD offers new insight into the factors that drive radical- and photon-directed processes. The location of a basic Arg site influences photon-activated C(α)-C(O) bond cleavages of singly charged peptide radical cations, an outcome attributed to the initial conformation of the peptide as supported by molecular dyna ...[more]

PMID: 22431222

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