2q2e
From Proteopedia
Crystal structure of the topoisomerase VI holoenzyme from Methanosarcina mazei
Overview
Type II topoisomerases help disentangle chromosomes to facilitate cell division. To advance understanding of the structure and dynamics of these essential enzymes, we have determined the crystal structure of an archaeal type IIB topoisomerase, topo VI, at 4.0-A resolution. The 220-kDa heterotetramer adopts a 'twin-gate' architecture, in which a pair of ATPase domains at one end of the enzyme is poised to coordinate DNA movements into the enzyme and through a set of DNA-cleaving domains at the other end. Small-angle X-ray scattering studies show that nucleotide binding elicits a major structural reorganization that is propagated to the enzyme's DNA-cleavage center, explaining how ATP is coupled to DNA capture and strand scission. These data afford important insights into the mechanisms of topo VI and related proteins, including type IIA topoisomerases and the Spo11 meiotic recombination endonuclease.
About this Structure
2Q2E is a Protein complex structure of sequences from Methanosarcina mazei. Full crystallographic information is available from OCA.
Reference
Holoenzyme assembly and ATP-mediated conformational dynamics of topoisomerase VI., Corbett KD, Benedetti P, Berger JM, Nat Struct Mol Biol. 2007 Jul;14(7):611-9. Epub 2007 Jul 1. PMID:17603498 Page seeded by OCA on Sun May 4 14:12:20 2008
