The effect of chemical modification of DNA base on binding of Hg-II and Ag-I in metal-mediated base pairs

0466107 - ÚOCHB 2017 RIV NL eng J - Journal Article
Šebera, Jakub - Tanaka, Y. - Ono, A. - Sychrovský, Vladimír
The effect of chemical modification of DNA base on binding of Hg-II and Ag-I in metal-mediated base pairs.
Inorganica chimica acta. Roč. 452, Oct 1 (2016), s. 199-204. ISSN 0020-1693. E-ISSN 1873-3255
R&D Projects: GA ČR GA13-27676S
Institutional support: RVO:61388963
Keywords : DFT * metal-mediated base pairs * Hg * Ag
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.002, year: 2016

The Gibbs free energy of formation of metallo-base pair was calculated for the base pairs composed of T, U, F, CN, C and I nucleosides and Hg-II and Ag-I metals. The effect of particular metal and the effect of pH on relative stabilization of metallo-base pairs were studied with calculated Gibbs free energies. The stability of Hg-mediated base pairs gradually decreased owing to the F and CN chemical modification of thymine at carbon C5 and owing to the imino to imidazole change of N3 nitrogen atom linked with Hg-II. The prevalence of Ag-I-stabilization versus Hg-II-stabilization was calculated for the metallo-base pairs composed of T, U, F, CN, C and I nucleosides where nucleophilicity of N3 nitrogen atom gradually decreased. The calculated relative stabilizations of metallo-base pairs agreed qualitatively with the increase in melting temperatures measured previously for respective duplexes upon adding Hg-II and Ag-I metals (Okamoto et al., 2009). The absolute magnitude of (1)J(Hg,N) and (2)J(N,N) coupling constants across metal-mediated linkage increased owing to F and CN modification of T and further increase of magnitudes off-couplings was calculated for imino to imidazole change of metal-bound nitrogen.
Permanent Link: http://hdl.handle.net/11104/0264505