沙佩罗宁的功能:通过强制展开折叠来折叠
M Shtilerman1, G H Lorimer, S W Englander
1The Johnson Research Foundation, Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
概括
在几秒钟内,GroEL chaperonin系统部分展开了错误折叠的蛋白质. 这一过程需要ATP水解,帮助蛋白质通过首先导致部分展开来重新折叠.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 蛋白质折叠 蛋白质的折叠
背景情况:
- 错误折叠的蛋白质可以积累并导致细胞功能障碍.
- 沙佩罗宁是帮助蛋白质折叠的分子机器.
- 目前尚不完全了解GroEL促进蛋白质展开和重新折叠的确切机制.
研究的目的:
- 为了研究GroEL chaperonin系统在错误折叠的基底蛋白中诱导展开的能力.
- 为了确定GroEL介导的展开的动力学和能量需求.
- 阐明部分展开在GroEL所促进的整体蛋白质折叠过程中的作用.
主要方法:
- 利用交换技术来监测蛋白质的结构变化.
- 研究了GroEL chaperonin系统及其基底蛋白.
- 分析了核三酸盐结合和腺三酸盐水解对展开过程的影响.
主要成果:
- 基质蛋白的GroEL诱导的展开是局部的,需要完整的Chaperonin系统.
- 展开发生在系统13秒的周转时间内.
- 核三酸盐结合为单个展开事件提供能量;多个转换取决于腺三酸盐水解.
- 基质蛋白释放发生在每次周转时,无论重新折叠状态如何.
- 格罗埃尔的结构似乎是优化生成机械力展开.
结论:
- GroEL通过诱导阻塞的,错误折叠的蛋白质的部分展开来促进蛋白质折叠.
- 陪伴者系统采用机械展开机制.
- 展开的能量由ATP水解提供,使代的展开和释放循环成为可能.
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