1MX0

Structure of topoisomerase subunit

Summary for 1MX0

• Entry DOI: 10.2210/pdb1mx0/pdb
• Related: 1MU5
• Descriptor: Type II DNA topoisomerase VI subunit B, MAGNESIUM ION, PHOSPHOAMINOPHOSPHONIC ACID-ADENYLATE ESTER, ... (5 entities in total)
• Functional Keywords: ghkl atpase, topoisomerase, isomerase
• Biological source: Sulfolobus shibatae
• Total number of polymer chains: 6
• Total formula weight: 327230.98

Authors

Corbett, K.D.,Berger, J.M. (deposition date: 2002-10-01, release date: 2003-01-07, Last modification date: 2024-10-16)

Primary citation

Corbett, K.D.,Berger, J.M.
Structure of the topoisomerase VI-B subunit: implications for type II topoisomerase mechanism and evolution
Embo J., 22:151-163, 2003

PubMed Abstract: Type IIA and type IIB topoisomerases each possess the ability to pass one DNA duplex through another in an ATP-dependent manner. The role of ATP in the strand passage reaction is poorly understood, particularly for the type IIB (topoisomerase VI) family. We have solved the structure of the ATP-binding subunit of topoisomerase VI (topoVI-B) in two states: an unliganded monomer and a nucleotide-bound dimer. We find that topoVI-B is highly structurally homologous to the entire 40-43 kDa ATPase region of type IIA topoisomerases and MutL proteins. Nucleotide binding to topoVI-B leads to dimerization of the protein and causes dramatic conformational changes within each protomer. Our data demonstrate that type IIA and type IIB topoisomerases have descended from a common ancestor and reveal how ATP turnover generates structural signals in the reactions of both type II topoisomerase families. When combined with the structure of the A subunit to create a picture of the intact topoisomerase VI holoenzyme, the ATP-driven motions of topoVI-B reveal a simple mechanism for strand passage by the type IIB topoisomerases.

PubMed: 12505993
DOI: 10.1093/emboj/cdg008

Experimental method

X-RAY DIFFRACTION (2.3 Å)