Jump to main content
Jump to site search


Photoactivated proton coupled electron transfer in DNA: insights from quantum mechanical calculations

Author affiliations

Abstract

The energetics of the two main proton coupled electron transfer processes that could occur in DNA are determined by means of time dependent-DFT calculations, using the M052X functional and the polarizable continuum model to include solvent effect. This approach has been applied to fragments of GC and AT alternated duplexes containing up to 4 base pairs. In GC DNA, intra-strand G → C charge transfer (CT) can trigger inter-strand Proton Transfer (PT) involving the C anion, since the reaction is exothermic and the related energy barrier is <0.3 eV. In AT DNA, the minimum resulting from intra-strand A → T CT is not predicted to undergo inter-strand PT. These conclusions are in full agreement with the indication of time-resolved IR spectra. In both systems, inter-strand CT can be coupled to inter-strand PT, and the resulting minimum, reached after overcoming a moderate energy barrier (<0.4 eV), is close to a crossing region with the ground electronic state, providing a relatively fast non-radiative deactivation route.

Graphical abstract: Photoactivated proton coupled electron transfer in DNA: insights from quantum mechanical calculations

Back to tab navigation

Supplementary files

Publication details

The article was received on 15 Sep 2017, accepted on 26 Sep 2017 and first published on 26 Sep 2017


Article type: Paper
DOI: 10.1039/C7FD00195A
Citation: Faraday Discuss., 2018, Advance Article
  •   Request permissions

    Photoactivated proton coupled electron transfer in DNA: insights from quantum mechanical calculations

    L. Martinez-Fernandez and R. Improta, Faraday Discuss., 2018, Advance Article , DOI: 10.1039/C7FD00195A

Search articles by author

Spotlight

Advertisements