Keniry M A, Gutowsky H S, Oldfield E
Nature. 1984;307(5949):383-6. doi: 10.1038/307383a0.
Recently, there has been great interest in determining the three-dimensional structures of membrane proteins, particularly bacteriorhodopsin, for which a variety of possible folding arrangements have been suggested. In this paper we present nuclear magnetic resonance (NMR) spectra of deuterated bacteriorhodopsin, and use the data to help interpret the various suggested bacteriorhodopsin folding patterns. The results strongly indicate that (1) a membrane surface (+/- 1 residue) may be defined by NMR in bacteriorhodopsin; (2) all amino acids inside the surface are essentially crystalline; (3) all amino acids outside the surface (surface residues) in bacteriorhodopsin are highly mobile on the time scale of the 2H NMR experiments; (4) NMR data may be used to help evaluate the various structural models that have been proposed; (5) aggregation of purple membrane sheets may lead to an immobilization of the surface residues.
最近，人们对确定膜蛋白的三维结构，尤其是细菌视紫红质的三维结构产生了浓厚兴趣，针对细菌视紫红质已经提出了多种可能的折叠排列方式。在本文中，我们展示了氘代细菌视紫红质的核磁共振（NMR）光谱，并利用这些数据来辅助解释各种提出的细菌视紫红质折叠模式。结果有力地表明：（1）通过NMR可以在细菌视紫红质中确定一个膜表面（±1个残基）；（2）该表面内的所有氨基酸基本呈结晶态；（3）细菌视紫红质中该表面外的所有氨基酸（表面残基）在2H NMR实验的时间尺度上具有高度流动性；（4）NMR数据可用于辅助评估已提出的各种结构模型；（5）紫膜片层的聚集可能导致表面残基固定化。
