Pervushin K V, Arseniev A S, Kozhich A T, Ivanov V T
M.M. Shemyakin Institute of Bioorganic Chemistry, U.S.S.R. Academy of Sciences, Moscow.
J Biomol NMR. 1991 Nov;1(4):313-22. doi: 10.1007/BF02192857.
The conformation of the synthetic 32-residue polypeptide, an analog of the membrane spanning segment B (residues 34-65) of Halobacterium halobium bacterioopsin, incorporated into perdeuterated sodium dodecyl sulfate micelles in the presence of trifluoroethanol was investigated by 1H NMR spectroscopy. The spectrum resonances were assigned by means of phase-sensitive DQF-COSY, TOCSY and NOESY techniques. Interproton nuclear Overhauser effects and deuterium exchange rates of individual NH groups were derived from two-dimensional NMR spectra. Analysis of the obtained data showed that segment B has a right-handed alpha-helical stretch from Lys41 to Leu62 with a kink at Pro50. The alpha-helix in the C-terminal part is terminated at Gly63, which adopts a conformation typical of amino acid residues in a left-handed helix. The N-terminal part (residues 34-40) has no ordered conformation. NMR data are provided for comparison of the segment B conformation in the isotropic system of an organic solvent, in SDS micelles and in the purple membrane bacterioopsin. Factors affecting the conformation of membrane spanning segment B in various milieus are discussed.
通过¹H NMR光谱研究了一种合成的32个残基的多肽（嗜盐菌细菌视紫红质跨膜片段B（残基34 - 65）的类似物）在三氟乙醇存在下掺入全氘代十二烷基硫酸钠胶束中的构象。通过相敏DQF - COSY、TOCSY和NOESY技术对光谱共振进行了归属。从二维NMR光谱中得出了质子间核Overhauser效应和各个NH基团的氘交换率。对所得数据的分析表明，片段B从Lys41到Leu62具有右手α - 螺旋延伸，在Pro50处有一个扭结。C末端部分的α - 螺旋在Gly63处终止，Gly63采用左手螺旋中氨基酸残基典型的构象。N末端部分（残基34 - 40）没有有序构象。提供了NMR数据，用于比较片段B在有机溶剂各向同性体系、SDS胶束和紫色膜细菌视紫红质中的构象。讨论了影响跨膜片段B在各种环境中构象的因素。
