Oxidative demethylation by Escherichia coli AlkB directly reverts DNA base damage

@article{Trewick2002OxidativeDB,
  title={Oxidative demethylation by Escherichia coli AlkB directly reverts DNA base damage},
  author={Sarah C. Trewick and Timothy F. Henshaw and Robert P. Hausinger and Tomas Lindahl and Barbara Sedgwick},
  journal={Nature},
  year={2002},
  volume={419},
  pages={174-178}
}
Methylating agents generate cytotoxic and mutagenic DNA damage. Cells use 3-methyladenine-DNA glycosylases to excise some methylated bases from DNA, and suicidal O6-methylguanine-DNA methyltransferases to transfer alkyl groups from other lesions onto a cysteine residue. Here we report that the highly conserved AlkB protein repairs DNA alkylation damage by means of an unprecedented mechanism. AlkB has no detectable nuclease, DNA glycosylase or methyltransferase activity; however, Escherichia… Expand
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