4MN4

Structural Basis for the MukB-topoisomerase IV Interaction

4MN4 の概要

• エントリーDOI: 10.2210/pdb4mn4/pdb
• 分子名称: DNA topoisomerase 4 subunit A, Chromosome partition protein MukB (3 entities in total)
• 機能のキーワード: beta-pinwheel, chromosome partitioning, isomerase-cell cycle complex, isomerase/cell cycle
• 由来する生物種: Escherichia coli; 詳細
• 細胞内の位置: Cell membrane; Peripheral membrane protein: P0AFI2; Cytoplasm, nucleoid: P22523
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 93286.21

構造登録者

Vos, S.M.,Stewart, N.K.,Oakley, M.G.,Berger, J.M. (登録日: 2013-09-09, 公開日: 2013-10-23, 最終更新日: 2024-11-06)

主引用文献

Vos, S.M.,Stewart, N.K.,Oakley, M.G.,Berger, J.M.
Structural basis for the MukB-topoisomerase IV interaction and its functional implications in vivo.
Embo J., 32:2950-2962, 2013

PubMed Abstract: Chromosome partitioning in Escherichia coli is assisted by two interacting proteins, topoisomerase (topo) IV and MukB. MukB stimulates the relaxation of negative supercoils by topo IV; to understand the mechanism of their action and to define this functional interplay, we determined the crystal structure of a minimal MukB-topo IV complex to 2.3 Å resolution. The structure shows that the so-called 'hinge' region of MukB forms a heterotetrameric assembly with a C-terminal DNA binding domain (CTD) on topo IV's ParC subunit. Biochemical studies show that the hinge stimulates topo IV by competing for a site on the CTD that normally represses activity on negatively supercoiled DNA, while complementation tests using mutants implicated in the interaction reveal that the cellular dependency on topo IV derives from a joint need for both strand passage and MukB binding. Interestingly, the configuration of the MukB·topo IV complex sterically disfavours intradimeric interactions, indicating that the proteins may form oligomeric arrays with one another, and suggesting a framework by which MukB and topo IV may collaborate during daughter chromosome disentanglement.

PubMed: 24097060
DOI: 10.1038/emboj.2013.218

実験手法

X-RAY DIFFRACTION (2.3 Å)