Download MendeleyCrystal structures of DNA/RNA repair enzymes AlkB and ABH2 bound to dsDNA
Yang, C.-G., Yi, C., Duguid, E.M., Sullivan, C.T., Jian, X., Rice, P.A., He, C.(2008) Nature 452: 961-965
- PubMed: 18432238
- DOI: https://doi.org/10.1038/nature06889
- Primary Citation of Related Structures:
3BI3, 3BIE, 3BKZ, 3BTX, 3BTY, 3BTZ, 3BU0, 3BUC - PubMed Abstract:
Escherichia coli AlkB and its human homologues ABH2 and ABH3 repair DNA/RNA base lesions by using a direct oxidative dealkylation mechanism. ABH2 has the primary role of guarding mammalian genomes against 1-meA damage by repairing this lesion in double-stranded DNA (dsDNA), whereas AlkB and ABH3 preferentially repair single-stranded DNA (ssDNA) lesions and can repair damaged bases in RNA. Here we show the first crystal structures of AlkB-dsDNA and ABH2-dsDNA complexes, stabilized by a chemical cross-linking strategy. This study reveals that AlkB uses an unprecedented base-flipping mechanism to access the damaged base: it squeezes together the two bases flanking the flipped-out one to maintain the base stack, explaining the preference of AlkB for repairing ssDNA lesions over dsDNA ones. In addition, the first crystal structure of ABH2, presented here, provides a structural basis for designing inhibitors of this human DNA repair protein.
Organizational Affiliation:
Department of Chemistry, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA.
