Download MendeleyCrystal structure of the amino-terminal fragment of vaccinia virus DNA topoisomerase I at 1.6 A resolution.
Sharma, A., Hanai, R., Mondragon, A.(1994) Structure 2: 767-777
- PubMed: 7994576
- DOI: https://doi.org/10.1016/s0969-2126(94)00077-8
- Primary Citation of Related Structures:
1VCC - PubMed Abstract:
Vaccinia virus, a cytoplasmically-replicating poxvirus, encodes a type I DNA topoisomerase that is biochemically similar to eukaryotic-like DNA topoisomerases I, and which has been widely studied as a model topoisomerase. It is the smallest topoisomerase known and is unusual in that it is resistant to the potent chemotherapeutic agent camptothecin. The crystal structure of a 9 kDa amino-terminal fragment of vaccinia virus DNA topoisomerase I has been determined at 1.6 A resolution. The fragment forms a five-stranded, antiparallel beta-sheet with two short alpha-helices and connecting loops. Residues that are conserved between all eukaryotic-like type I topoisomerases are not clustered in particular regions of the structure. This is the first atomic structure of any region of a eukaryotic-like DNA topoisomerase I. It has provided insights into the structural bases of the phenotypes of some single-site mutants of the intact topoisomerase. The structure has enabled us to study the interactions within a well-folded protein fragment and the camptothecin resistance of the viral topoisomerase.
Organizational Affiliation:
Department of Biochemistry, Molecular Biology and Cell Biology, Northwestern University, Evanston, IL 60208-3500.
