Directed evolution of substrate-optimized GroEL/S chaperonins
Directed evolution of substrate-optimized GroEL/S chaperonins
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DOI：
10.1016/s0092-8674(02)01198-4
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发表时间：
2002-12-27
期刊：
影响因子：
64.5
通讯作者：
Weissman, JS
中科院分区：
文献类型：
--
作者：
Wang, JD;Herman, C;Weissman, JS
GroEL/S伴侣蛋白环复合物折叠许多不相关的蛋白质。为了了解伴侣蛋白底物谱的基础和范围，我们使用了多轮选择和DNA改组来获得GroEL/S变体，其显著增强了单个底物绿色荧光蛋白（GFP）的折叠。底物优化的伴侣蛋白的变化增加了折叠腔的极性并改变了ATP酶循环。这些发现揭示了GroEL/S的令人惊讶的可塑性，其可用于帮助重组蛋白的折叠。我们的研究还揭示了伴侣蛋白的特化和泛化之间的冲突，因为GFP折叠的增加是以GroEL/S折叠其天然底物的能力为代价的。这种冲突和环状结构的性质可能有助于解释细胞伴侣系统的进化。
GroEL/S chaperonin ring complexes fold many unrelated proteins. To understand the basis and extent of the chaperonin substrate spectrum, we used rounds of selection and DNA shuffling to obtain GroEL/S variants that dramatically enhanced folding of a single substrate-green fluorescent protein (GFP). Changes in the substrate-optimized chaperonins increase the polarity of the folding cavity and alter the ATPase cycle. These findings reveal a surprising plasticity of GroEL/S, which can be exploited to aid folding of recombinant proteins. Our studies also reveal a conflict between specialization and generalization of chaperonins as increased GFP folding comes at the expense of the ability of GroEL/S to fold its natural substrates. This conflict and the nature of the ring structure may help explain the evolution of cellular chaperone systems.