Solution structure of a minor and transiently formed state of a T4 lysozyme mutant.
Solution structure of a minor and transiently formed state of a T4 lysozyme mutant.
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DOI：
10.1038/nature10349
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发表时间：
2011-08-21
期刊：
影响因子：
64.8
通讯作者：
Kay, Lewis E.
中科院分区：
文献类型：
--
作者：
Bouvignies, Guillaume;Vallurupalli, Pramodh;Hansen, D. Flemming;Correia, Bruno E.;Lange, Oliver;Bah, Alaji;Vernon, Robert M.;Dahlquist, Frederick W.;Baker, David;Kay, Lewis E.
蛋白质是固有的可塑性分子，其功能通常严重依赖于不同分子构象（构象异构体）之间的偏移。然而，对蛋白质结构、动力学和功能之间关系的严格理解仍然是难以捉摸的。这是因为其能量景观中的许多构象只是短暂形成和少量填充（不到分子总数的百分之几），因此它们不能被大多数生物物理工具单独表征。在这里，我们研究了来自噬菌体T4的溶菌酶突变体，该突变体结合疏水性分子并在25 °C下瞬时（约1 ms）填充激发态至约3%（参考文献）。我们表明，这种结合只发生在基态，并提出了原子级模型的“不可见”，激发态获得使用弛豫色散NMR（参考）的组合策略。和CS-Rosetta模型的建立，合理化这一观察。该模型进行了测试，使用基于结构的设计计算确定点突变体预测稳定的激发态相对于基态。通过这种方式，引入了一对突变，反转了基态和激发态的相对群体并改变了功能。我们的研究结果表明，通过改变其能量景观状态之间的微妙平衡，蛋白质功能的进化机制。更一般地说，他们表明，我们的方法可以生成和验证激发蛋白质状态的模型。
Proteins are inherently plastic molecules, whose function often critically depends on excursions between different molecular conformations (conformers). However, a rigorous understanding of the relation between a protein’s structure, dynamics and function remains elusive. This is because many of the conformers on its energy landscape are only transiently formed and marginally populated (less than a few per cent of the total number of molecules), so that they cannot be individually characterized by most biophysical tools. Here we study a lysozyme mutant from phage T4 that binds hydrophobic molecules and populates an excited state transiently (about 1 ms) to about 3% at 25 °C (ref.). We show that such binding occurs only via the ground state, and present the atomic-level model of the ‘invisible’, excited state obtained using a combined strategy of relaxation-dispersion NMR (ref.) and CS-Rosetta model building that rationalizes this observation. The model was tested using structure-based design calculations identifying point mutants predicted to stabilize the excited state relative to the ground state. In this way a pair of mutations were introduced, inverting the relative populations of the ground and excited states and altering function. Our results suggest a mechanism for the evolution of a protein’s function by changing the delicate balance between the states on its energy landscape. More generally, they show that our approach can generate and validate models of excited protein states.
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影响因子：
56.9
作者：
Korzhnev, Dmitry M.;Religa, Tomasz L.;Kay, Lewis E.
通讯作者：
Kay, Lewis E.
影响因子：
15
作者：
Hu, JS;Bax, A
通讯作者：
Bax, A
DOI：
10.1073/pnas.0610313104
发表时间：
2007-06-05
影响因子：
11.1
作者：
Cavalli, Andrea;Salvatella, Xavier;Vendruscolo, Michele
通讯作者：
Vendruscolo, Michele
影响因子：
56.9
作者：
Boehr, David D.;McElheny, Dan;Wright, Peter E.
通讯作者：
Wright, Peter E.
DOI：
10.1038/nsb0696-516
发表时间：
1996-06-01
期刊：
NATURE STRUCTURAL BIOLOGY
影响因子：
--
作者：
Feher, VA;Baldwin, EP;Dahlquist, FW
通讯作者：
Dahlquist, FW