Dual function of protein confinement in chaperonin-assisted protein folding
Dual function of protein confinement in chaperonin-assisted protein folding
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DOI：
10.1016/s0092-8674(01)00517-7
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发表时间：
2001-10-19
期刊：
影响因子：
64.5
通讯作者：
Hayer-Hartl, M
中科院分区：
文献类型：
--
作者：
Brinker, A;Pfeifer, G;Hayer-Hartl, M
GroEL/GroES伴侣蛋白系统介导细菌胞质溶胶中一系列新合成多肽的折叠。使用基于快速生物素-链霉亲和素的伴侣蛋白功能抑制，我们表明由GroEL及其辅因子GroES形成的笼可以在促进折叠中具有双重作用。首先，GroEL：GroES复合物中的非天然蛋白质的封闭对于折叠以不受聚集损害地进行是必不可少的。其次，与GroES结合和释放的ATP驱动循环无关，笼内折叠比自由溶液中的折叠要快得多。这表明，未折叠蛋白质在伴侣蛋白笼的狭窄亲水空间中的限制使一些蛋白质折叠的能量景观平滑，增加了折叠中间体向天然状态的通量。
The GroEL/GroES chaperonin system mediates the folding of a range of newly synthesized polypeptides in the bacterial cytosol. Using a rapid biotin-streptavidin-based inhibition of chaperonin function, we show that the cage formed by GroEL and its cofactor GroES can have a dual role in promoting folding. First, enclosure of nonnative protein in the GroEL:GroES complex is essential for folding to proceed unimpaired by aggregation. Second, folding inside the cage can be significantly faster than folding in free solution, independently of ATP-driven cycles of GroES binding and release. This suggests that confinement of unfolded protein in the narrow hydrophilic space of the chaperonin cage smoothes the energy landscape for the folding of some proteins, increasing the flux of folding intermediates toward the native state.