Marsh Joseph A, Baker Jennifer M R, Tollinger Martin, Forman-Kay Julie D
Molecular Structure & Function, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada.
J Am Chem Soc. 2008 Jun 25;130(25):7804-5. doi: 10.1021/ja802220c. Epub 2008 May 31.
Residual dipolar couplings (RDCs) have been observed in disordered states of several proteins. While their nonuniform values were initially surprising, it has been shown that reasonable approximation of experimental RDCs can be obtained using simple statistical coil models and assuming global alignment of each structure, provided that many thousands of conformers are averaged. Here we show that, by using short local alignment tensors, we can achieve good agreement between experimental and simulated RDCs with far fewer structures than required when using global alignment. This makes the possibility of using RDCs as direct restraints in structural calculations of disordered proteins much more feasible. In addition, it provides insight into the nature of RDCs in disordered states, suggesting that they are primarily reporting on local structure.
在几种蛋白质的无序状态中已观察到剩余偶极耦合（RDCs）。虽然其不均匀的值最初令人惊讶，但已表明，只要对数千个构象进行平均，使用简单的统计卷曲模型并假设每个结构的全局排列，就可以得到实验RDCs的合理近似值。在这里，我们表明，通过使用短的局部排列张量，我们可以在实验和模拟的RDCs之间取得良好的一致性，而所需的结构数量远少于使用全局排列时的要求。这使得将RDCs用作无序蛋白质结构计算中的直接约束条件的可能性变得更加可行。此外，它还深入了解了无序状态下RDCs的性质，表明它们主要反映的是局部结构。
