Theoretical and experimental study of charge transfer through DNA: impact of mercury mediated T-Hg-T base pair.
DNA-Hg complexes may play an important role in sensing DNA defects or in detecting the presence of Hg in the environment. A fundamental way of characterizing DNA-Hg complexes is to study the way the electric charge is transferred through the molecular chain. The main goal of this contribution was to investigate the impact of a mercury metal cation that links two thymine bases in a DNA T-T mismatched base pair (T-Hg-T) on charge transfer through the DNA molecule. We compared the charge transfer efficiencies in standard DNA, DNA with mismatched T-T base pairs, and DNA with a T-Hg(II)-T base pair. For this purpose, we measured the temperature dependence of steady-state fluorescence and UV-vis of the DNA molecules. The experimental results were confronted with the results obtained employing theoretical DFT methods. Generally, the efficiency of charge transfer was driven by mercury changing the spatial overlap of bases.
Institute of Physics, Academy of Sciences of the Czech Republic , v.v.i, Na Slovance 2, CZ-182 21 Prague 8, Czech Republic.
Irena
I
Kratochvílová
Martin
M
Golan
Martin
M
Vala
Miroslava
M
Špérová
Martin
M
Weiter
Ondřej
O
Páv
Jakub
J
Šebera
Ivan
I
Rosenberg
Vladimír
V
Sychrovský
Yoshiyuki
Y
Tanaka
F Matthias
FM
Bickelhaupt
D020029:Base Pairing; D002412:Cations / Q000737:chemistry; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D008628:Mercury / Q000737:chemistry*; D008962:Models, Theoretical; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D013941:Thymine / Q000737:chemistry*
D002412:Cations; D004247:DNA; D008628:Mercury; D013941:Thymine