Download MendeleyStructural basis for nick recognition by a minimal pluripotent DNA ligase.
Nair, P.A., Nandakumar, J., Smith, P., Odell, M., Lima, C.D., Shuman, S.(2007) Nat Struct Mol Biol 14: 770-778
- PubMed: 17618295
- DOI: https://doi.org/10.1038/nsmb1266
- Primary Citation of Related Structures:
2Q2T, 2Q2U - PubMed Abstract:
Chlorella virus DNA ligase, the smallest eukaryotic ligase known, has pluripotent biological activity and an intrinsic nick-sensing function, despite having none of the accessory domains found in cellular ligases. A 2.3-A crystal structure of the Chlorella virus ligase-AMP intermediate bound to duplex DNA containing a 3'-OH-5'-PO4 nick reveals a new mode of DNA envelopment, in which a short surface loop emanating from the OB domain forms a beta-hairpin 'latch' that inserts into the DNA major groove flanking the nick. A network of interactions with the 3'-OH and 5'-PO4 termini in the active site illuminates the DNA adenylylation mechanism and the crucial roles of AMP in nick sensing and catalysis. Addition of a divalent cation triggered nick sealing in crystallo, establishing that the nick complex is a bona fide intermediate in the DNA repair pathway.
Organizational Affiliation:
Molecular Biology and Structural Biology Programs, Sloan-Kettering Institute, New York, New York 10021, USA.
