Oxidation Half-Reaction of Aqueous Nucleosides and Nucleotides via Photoelectron Spectroscopy Augmented by ab Initio Calculations

0443310 - ÚOCHB 2016 RIV US eng J - Journal Article
Schroeder, C. A. - Pluhařová, Eva - Seidel, R. - Schroeder, W. P. - Faubel, M. - Slavíček, P. - Winter, B. - Jungwirth, Pavel - Bradforth, S. E.
Oxidation Half-Reaction of Aqueous Nucleosides and Nucleotides via Photoelectron Spectroscopy Augmented by ab Initio Calculations.
Journal of the American Chemical Society. Roč. 137, č. 1 (2015), s. 201-209. ISSN 0002-7863. E-ISSN 1520-5126
R&D Projects: GA ČR GBP208/12/G016
Grant - others:GA ČR(CZ) GA13-34168S
Institutional support: RVO:61388963
Keywords : DNA damage * photoelectron spectroscopy * DNA charge migration
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 13.038, year: 2015
http://pubs.acs.org/doi/10.1021/ja508149e

Oxidative damage to DNA and hole transport between nucleobases in oxidized DNA are important processes in lesion formation for which surprisingly poor thermodynamic data exist, the relative ease of oxidizing the four nucleobases being one such example. Theoretical simulations of radiation damage and charge transport in DNA depend on accurate values for vertical ionization energies (VIEs), reorganization energies, and standard reduction potentials. Liquid-jet photoelectron spectroscopy can be used to directly study the oxidation half-reaction. The VIEs of nucleic acid building blocks are measured in their native buffered aqueous environment. The experimental investigation of purine and pyrimidine nucleotides, nucleosides, pentose sugars, and inorganic phosphate demonstrates that photoelectron spectra of nucleotides arise as a spectral sum over their individual chemical components; that is, the electronic interactions between each component are effectively screened from one another by water. Electronic structure theory affords the assignment of the lowest energy photoelectron band in all investigated nucleosides and nucleotides to a single ionizing transition centered solely on the nucleobase. Thus, combining the measured VIEs with theoretically determined reorganization energies allows for the spectroscopic determination of the one-electron redox potentials that have been difficult to establish via electrochemistry.
Permanent Link: http://hdl.handle.net/11104/0246079