DFT calculations on the deprotonation site of the one-electron oxidised guanine–cytosinebase pair

文献情報

出版日 2010-06-08

DOI 10.1039/C002528C

インパクトファクター 3.676

著者

Steen Steenken, Jóhannes Reynisson

原文を見る

要旨

As calculated by the density functional theory (DFT), the acidity of cytosine's exocyclic amine group (C–N4H2) in the base pair G–C is considerably increased upon its one-electron oxidation. The proton affinity (PA) of the amine moiety is lowered by ionisation of G–C (which yields G˙+–C) from −348.1 to −269.1 kcal mol−1. The PA is further decreased by 7.6 kcal mol−1 as a result of the ensuing proton transfer from G˙+ to C to yield the spin–charge separated base pair G(−H)˙–C(+H)+. Under these conditions and taking the hydration energy of H+ into account, the overall proton transfer from the C–N4H2 group to the aqueous phase in the major groove is exothermic by −2.4 kcal mol−1. This proton transfer to water from the initially present DNA radical cation constitutes separation of charge from spin and thus reduces positive charge transfer in double stranded DNA.

掲載誌

Physical Chemistry Chemical Physics

CiteScore: 5.5

自己引用率: 10.3%

年間論文数: 3036

Physical Chemistry Chemical Physics (PCCP) is an international journal co-owned by 19 physical chemistry and physics societies from around the world. This journal publishes original, cutting-edge research in physical chemistry, chemical physics and biophysical chemistry. To be suitable for publication in PCCP, articles must include significant innovation and/or insight into physical chemistry; this is the most important criterion that reviewers and Editors will judge against when evaluating submissions. The journal has a broad scope and welcomes contributions spanning experiment, theory, computation and data science. Topical coverage includes spectroscopy, dynamics, kinetics, statistical mechanics, thermodynamics, electrochemistry, catalysis, surface science, quantum mechanics, quantum computing and machine learning. Interdisciplinary research areas such as polymers and soft matter, materials, nanoscience, energy, surfaces/interfaces, and biophysical chemistry are welcomed if they demonstrate significant innovation and/or insight into physical chemistry. Joined experimental/theoretical studies are particularly appreciated when complementary and based on up-to-date approaches.