对细菌凝聚酶复合物的结构研究揭示了ATP依赖的ATP之间的互动相互作用的破坏
Jae-Sung Woo1, Jae-Hong Lim, Ho-Chul Shin
1Center for Biomolecular Recognition and Division of Molecular and Life Science, Department of Life Sciences, Pohang University of Science and Technology, Pohang, Kyungbuk, 790-784, Korea.
Cell
|January 13, 2009
概括
细菌的凝聚酶复合体MUKBEF
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- 凝聚素是所有生物体中染色体凝聚的重要蛋白质复合体.
- 细菌的MukBEF复合体,是真核凝聚物的同类,包括SMC蛋白MUKB和子单元MUKE和MUKF.
研究的目的:
- 为了阐明 MukBEF 凝聚酶复合体内的完整结构相互作用.
- 研究MukB的ATPase活性在该复合物的功能中的作用.
主要方法:
- 进行X射线晶体学以确定MukBEF复合体的结构.
- 生物化学试验用于研究MukB.的ATPase活性.
- 位点定向突变发生,以分析特定域和链接器的功能.
主要成果:
- 完整的结构视图显示,Muke和MukeF形成一个二维框架,MukeF的C端翼螺旋域 (C-WHDs) 绑定MukeB头以形成环状结构.
- 通过ATP介导的MukB头的接触导致一个MukF C-WHD脱离,破坏了环结构.
- 在C-WHD之前的左侧部分的突变损害了这种脱落,并限制了细胞生长.
结论:
- 根据ATP,MukB-MukF相互作用的暂时中断是凝聚酶功能的一个关键方面.
- 这种动态的结构变化,在凝聚酶环中产生开口,可能对由MukBEF复合体介导的染色体凝聚是至关重要的.
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