8-Oxoguanine Forms Quartets with a Large Central Cavity.
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ABSTRACT:
SUBMITTER: Aleksic S
PROVIDER: S-EPMC9631995 | biostudies-literature | 2022 Nov
REPOSITORIES: biostudies-literature
Publications
8-Oxoguanine Forms Quartets with a Large Central Cavity.
Aleksič Simon S Podbevšek Peter P Plavec Janez J
Biochemistry 20221019 21
Oxidation of a guanine nucleotide in DNA yields an 8-oxoguanine nucleotide (<sup>oxo</sup>G) and is a mutagenic event in the genome. Due to different arrangements of hydrogen-bond donors and acceptors, <sup>oxo</sup>G can affect the secondary structure of nucleic acids. We have investigated base pairing preferences of <sup>oxo</sup>G in the core of a tetrahelical G-quadruplex structure, adopted by analogues of d(TG<sub>4</sub>T). Using spectroscopic methods, we have shown that G-quartets can be ...[more]
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