Proteome-wide analysis of chaperonin-dependent protein folding in Escherichia coli
Proteome-wide analysis of chaperonin-dependent protein folding in Escherichia coli
复制标题
DOI：
10.1016/j.cell.2005.05.028
复制
发表时间：
2005-07-29
期刊：
影响因子：
64.5
通讯作者：
Hartl, FU
中科院分区：
文献类型：
--
作者：
Kerner, MJ;Naylor, DJ;Hartl, FU
大肠杆菌伴侣蛋白GroEL及其辅因子GroEL通过将外来多肽隔离在笼状结构中来促进蛋白质折叠。在这里，我们定义了这个系统对整个大肠杆菌蛋白质组的蛋白质折叠的贡献。大约有250种不同的蛋白质与GroEL相互作用，但大多数蛋白质可以利用GroEL或上游伴侣触发因子(Tf)和DNAK进行折叠。专性GroEL依赖仅限于85种底物，包括13种必需蛋白质，占据了GroEL容量的75%以上。这些蛋白质似乎在折叠过程中以动力学方式聚集在捕获的中间产物中；它们被TF/DNAK稳定在抗聚集状态，但只有在转移到GroEL/GroES时才达到自然状态。有趣的是，在GroEL底物中大量富含具有(βα)(8)Tim-Barrel结构域的蛋白质。我们认为，伴侣系统可能促进了该折叠的进化，成为实现多种酶功能的多功能平台。
The E. coli chaperonin GroEL and its cofactor GroES promote protein folding by sequestering nonnative polypeptides in a cage-like structure. Here we define the contribution of this system to protein folding across the entire E. coli proteome. Approximately 250 different proteins interact with GroEL, but most of these can utilize either GroEL or the upstream chaperones trigger factor (TF) and DnaK for folding. Obligate GroEL-dependence is limited to only similar to 85 substrates, including 13 essential proteins, and occupying more than 75% of GroEL capacity. These proteins appear to populate kinetically trapped intermediates during folding; they are stabilized by TF/DnaK against aggregation but reach native state only upon transfer to GroEL/GroES. Interestingly, substantially enriched among the GroEL substrates are proteins with (beta alpha)(8) TIM-barrel domains. We suggest that the chaperonin system may have facilitated the evolution of this fold into a versatile platform for the implementation of numerous enzymatic functions.