Fleming Kieran, Matthews Stephen
Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London, UK.
Methods Mol Biol. 2004;278:79-88. doi: 10.1385/1-59259-809-9:079.
Measurement of residual dipolar couplings for proteins in nuclear magnetic resonance (NMR) requires a degree of molecular alignment. This may be achieved through the use of liquid crystals or compressed hydrated gels. Several media have been described in the literature, and this chapter describes five of the most commonly used systems. For two of these systems, bicelles and filamentous bacteriophage, the media can be purchased in a form ready for experiments. The remainder must be made by the investigator, yet they are generally straightforward to synthesize in the laboratory. Poly(ethylene glycol)/alcohol mixtures and Helfrich phases are made by simply mixing the ingredients in the correct manner, and strained gels use techniques familiar to all molecular biologists.
在核磁共振（NMR）中测量蛋白质的剩余偶极耦合需要一定程度的分子排列。这可以通过使用液晶或压缩水合凝胶来实现。文献中已经描述了几种介质，本章介绍五种最常用的体系。对于其中两种体系，即双分子层和丝状噬菌体，介质可以以准备好用于实验的形式购买。其余的必须由研究者制备，但它们通常在实验室中很容易合成。聚乙二醇/醇混合物和赫尔弗里希相通过简单地以正确方式混合成分来制备，而应变凝胶则使用所有分子生物学家都熟悉的技术。
