This article continues our review of spectroscopic studies of G-protein-coupled receptors. Magnetic resonance methods including electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) provide specific structural and dynamical data for the protein in conjunction with optical methods (vibrational, electronic spectroscopy) as discussed in the accompanying article. An additional advantage is the opportunity to explore the receptor proteins in the natural membrane lipid environment. Solid-state ²H and ¹³C NMR methods yield information about both the local structure and dynamics of the cofactor bound to the protein and its light-induced changes. Complementary site-directed spin-labeling studies monitor the structural alterations over larger distances and correspondingly longer time scales. A multiscale reaction mechanism describes how local changes of the retinal cofactor unlock the receptor to initiate large-scale conformational changes of rhodopsin. Activation of the G-protein-coupled receptor involves an ensemble of conformational substates within the rhodopsin manifold that characterize the dynamically active receptor.

中文翻译：

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凝聚态光谱法研究G蛋白偶联受体视紫红质。二。磁共振方法。

本文继续我们对G蛋白偶联受体的光谱研究的评论。如随附文章中所述，包括电子顺磁共振（EPR）和核磁共振（NMR）在内的磁共振方法可结合光学方法（振动，电子光谱）为蛋白质提供特定的结构和动力学数据。另一个优点是有机会在天然膜脂质环境中探索受体蛋白。固态² H和¹³13 C NMR方法可得出有关与蛋白质结合的辅因子及其光诱导变化的局部结构和动力学的信息。互补的定点自旋标记研究可监测较大距离和相应较长时间范围内的结构变化。多尺度反应机制描述了视网膜辅因子的局部变化如何解锁受体以引发视紫红质的大规模构象变化。G蛋白偶联受体的激活涉及视紫红质歧管内的构象亚状态的整体，其表征了动态活性受体。