对称与不对称的GroEL-GroES chaperonin复合物的功能意义
A Engel1, M K Hayer-Hartl, K N Goldie
1Maurice E. Müller Institute, Biozentrum, University of Basel, Switzerland.
概括
大肠杆菌的指挥素GroEL及其调节剂GroES形成了不对称的蛋白质折叠复合体. 最近被认为是功能性的对称复合体,需要非生理条件,并防止基质结合,质疑它们的意义.
科学领域:
- 分子生物学分子生物学
- 蛋白质折叠 蛋白质的折叠
- 生物化学 生物化学
背景情况:
- 大肠杆菌的Chaperonin GroEL及其Cochaperonin GroES对于蛋白质折叠至关重要.
- 传统上人们认为它们作为不对称的复合体起作用,在GroEL圆柱体内封装基质蛋白.
- 一个最近的假设提出了对称的GroEL: ((GroES) 2复合体作为功能单元,在外面与基质结合.
研究的目的:
- 研究对称GroEL:(GroES) 2复合体的形成和功能相关性.
- 确定对称复合体组合的条件.
- 为了评估对称复合体的基质结合能力.
主要方法:
- 电子显微镜的电子显微镜
- 生物化学分析的分析.
- 在体外组装测定试验.
主要成果:
- 对称的GroEL: ((GroES) 2复合体需要非生理学上高度和高pH值进行组装.
- 这些对称复合物的形成抑制了未折叠的多的结合.
- 这些发现挑战了对称复合体所提出的功能作用.
结论:
- 对称的GroEL:(GroES) 2复合体的组合取决于非生理条件.
- 对称复合体无法与未折叠的基质蛋白结合,这表明在体内缺乏功能相关性.
- 在蛋白质折叠中GroEL: ((GroES) 2颗粒的功能意义仍然未被证明.
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