折叠室关闭的机制在一个 II 组 chaperonin 中
Junjie Zhang1, Matthew L Baker, Gunnar F Schröder
1Graduate Program in Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, Texas 77030, USA.
Nature
|January 22, 2010
概括
第二组的沙佩罗宁使用ATP水解来关闭它们的盖子,从而促进蛋白质折叠. 这项研究使用冷电磁和计算建模揭示了这种形状变化的原子细节.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 第二组的沙佩罗宁是大型的,必不可少的蛋白质机器,参与细胞蛋白质折叠.
- 它们的功能依赖于由ATP水解触发的盖子机制,但根本的结构动力学是未知的.
研究的目的:
- 为了阐明结构重组和分子事件导致盖子关闭在II组Chaperonins.
- 提供第一个 II 组沙佩罗宁在其封闭的构造中的原子模型.
主要方法:
- 单颗粒冷电子显微镜 (cryo-EM) 用于确定一个古物II组Chaperonin (Mm-cpn) 的结构.
- 获得了四个结构,代表无核酸 (开放) 和核酸诱导 (关闭) 状态.
- 使用可变形弹性网络建模来完善开放的形状模型.
主要成果:
- 高分辨率的冷EM结构揭示了封闭构造的原子细节,包括核酸结合和侧链可视化.
- 开放和封闭的结构说明了ATP水解如何诱导局部形状变化,改变子单元间的接触.
- 这些变化驱动着摇运动,导致盖子关闭,这对于司机的功能至关重要.
结论:
- 由ATP水解引发的局部形状变化协调了II组Chaperonin形状循环所必需的全沟通和环间信号传输.
- 结合的冷电磁和计算建模方法为研究溶液中的动态宏分子机器提供了强大的方法.
相关概念视频
Molecular Chaperones and Protein Folding
The native conformation of a protein is formed by interactions between the side chains of its constituent amino acids. When the amino acids cannot form these interactions, the protein cannot fold by itself and needs chaperones. Notably, chaperones do not relay any additional information required for the folding of polypeptides; the native conformation of a protein is determined solely by its amino acid sequence. Chaperones catalyze protein folding without being a part of the folded protein.
The...
The...
Molecular Chaperones and Protein Folding
The native conformation of a protein is formed by interactions between the side chains of its constituent amino acids. When the amino acids cannot form these interactions, the protein cannot fold by itself and needs chaperones. Notably, chaperones do not relay any additional information required for the folding of polypeptides; the native conformation of a protein is determined solely by its amino acid sequence. Chaperones catalyze protein folding without being a part of the folded protein.
The...
The...
Protein Folding
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Folding
Overview
Protein Folding
Overview
Bacterial Protein Maturation
Bacterial protein maturation is a tightly regulated process that ensures newly synthesized polypeptides achieve correct functional conformations. This maturation involves a series of modifications, folding events, and quality control steps, often assisted by specialized chaperone proteins.N-Terminal ModificationsThe maturation of bacterial polypeptides begins cotranslationally as the polypeptide exits the ribosome. The first amino acid, N-formylmethionine (fMet), is typically modified at the...


