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PubMed · 17048919

Electronic coupling mediated by stacked [Thymine-Hg-Thymine] base pairs.

Alexander A Voityuk
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Abstract

Very recently it has been shown that stable metal-mediated base pairs [Thymine-Hg-Thymine] can form in DNA. To estimate the effect of such pairs on the efficiency of charge transfer through DNA, we carry out quantum mechanical calculations of double-stranded pi-stacks GXG, GXXG, and GXXXG, where X = [Thymine-Hg-Thymine] and stacks GT(n)G of canonical base pairs. The charge-transfer efficiency in short duplexes GXG and GTG is found to be similar. However, the donor-acceptor coupling in GXXG and GXXXG is stronger by a factor of 2.5-3.0 than that in GT(n)G (n = 2 and 3), respectively. It is shown that the valence orbitals of Hg atoms do not essentially participate in mediating the electronic coupling for hole transfer; however, they may play an important role in excess electron transfer.

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Base PairingDNAElectronsMercuryThymineJournal ArticleResearch Support, Non-U.S. Gov't

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Alexander A Voityuk. 2006-10-26. Electronic coupling mediated by stacked [Thymine-Hg-Thymine] base pairs.. https://doi.org/10.1021/jp062776d

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