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Crystal structure of a DNA duplex cross-linked by 6-thioguanine-6-thioguanine disulfides: reversible formation and cleavage catalyzed by Cu(ii) ions and glutathione.

ABSTRACT: Herein, we determined the crystal structure of a DNA duplex containing consecutive 6-thioguanine-6-thioguanine disulfides. The disulfide bonds were reversibly formed and cleaved in the presence of Cu(ii) ions and glutathione. To our knowledge, this is the first reaction in which metal ions efficiently accelerated disulfide bond formation between thio-bases in duplexes.

SUBMITTER: Ono A

PROVIDER: S-EPMC9067110 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Crystal structure of a DNA duplex cross-linked by 6-thioguanine-6-thioguanine disulfides: reversible formation and cleavage catalyzed by Cu(ii) ions and glutathione.

Ono Akira A Atsugi Takahiro T Goto Misato M Saneyoshi Hisao H Tomori Takahito T Seio Kohji K Dairaku Takenori T Kondo Jiro J

RSC advances 20190724 40

Herein, we determined the crystal structure of a DNA duplex containing consecutive 6-thioguanine-6-thioguanine disulfides. The disulfide bonds were reversibly formed and cleaved in the presence of Cu(ii) ions and glutathione. To our knowledge, this is the first reaction in which metal ions efficiently accelerated disulfide bond formation between thio-bases in duplexes. ...[more]

PMID: 35514505

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Effect of 6-thioguanine on the stability of duplex DNA.

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