Visualizing chaperone-assisted protein folding.
Visualizing chaperone-assisted protein folding.
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可视化伴侣辅助的蛋白质折叠。
DOI：
10.1038/nsmb.3237
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发表时间：
2016-07
影响因子：
16.8
通讯作者：
Bardwell JC
中科院分区：
文献类型：
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作者：
Horowitz S;Salmon L;Koldewey P;Ahlstrom LS;Martin R;Quan S;Afonine PV;van den Bedem H;Wang L;Xu Q;Trievel RC;Brooks CL 3rd;Bardwell JC
在确定异质性和动态蛋白质复合物的结构的挑战，极大地阻碍了过去的努力，以获得许多重要的生物过程的机械理解。一个这样的过程是伴侣辅助蛋白质折叠，其中获得伴侣：底物复合物的结构集合将最终揭示伴侣如何帮助蛋白质折叠成其天然状态。为了解决这个问题，我们设计了一种基于X射线晶体学的新型结构生物学方法，称为剩余电子和异常密度（READ）。READ使我们能够可视化即使是稀疏分布的构象的底物蛋白免疫蛋白7（Im7）与E。大肠杆菌伴侣蛋白这项研究产生了一系列快照，描绘了与Spy结合时Im7的各种折叠状态。合奏表明，间谍相关的Im7样品构象范围从未折叠到部分折叠和天然的状态，并揭示了如何基板可以探索其折叠景观，而绑定到伴侣。
Challenges in determining the structures of heterogeneous and dynamic protein complexes have greatly hampered past efforts to obtain a mechanistic understanding of many important biological processes. One such process is chaperone-assisted protein folding, where obtaining structural ensembles of chaperone:substrate complexes would ultimately reveal how chaperones help proteins fold into their native state. To address this problem, we devised a novel structural biology approach based on X-ray crystallography, termed Residual Electron and Anomalous Density (READ). READ enabled us to visualize even sparsely populated conformations of the substrate protein immunity protein 7 (Im7) in complex with the E. coli chaperone Spy. This study resulted in a series of snapshots depicting the various folding states of Im7 while bound to Spy. The ensemble shows that Spy-associated Im7 samples conformations ranging from unfolded to partially folded and native-like states, and reveals how a substrate can explore its folding landscape while bound to a chaperone.