31P-NMR studies of oriented multilayers formed from isolated sarcoplasmic reticulum and reconstituted sarcoplasmic reticulum.
31P-NMR studies of oriented multilayers formed from isolated sarcoplasmic reticulum and reconstituted sarcoplasmic reticulum.
复制标题
由分离的肌浆网和重建的肌浆网形成的定向多层的 31P-NMR 研究。
DOI：
10.1016/0005-2736(81)90214-5
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Fleischer,S
中科院分区：
文献类型：
--
作者：
McLaughlin,AC;Herbette,L;Blasie,JK;Wang,CT;Hymel,L;Fleischer,S
摘要31 P-NMR谱是从正常肌浆网和重组肌浆网的定向多层制备物中获得的，脂质与蛋白质的比例在42：1和110：1之间变化。31 P-NMR光谱对膜相对于磁场的排列的依赖性被用来得出两个关于对所观察到的光谱有贡献的磷脂分子的运动的结论。首先，磷酸基团和两个相邻的亚甲基基团能够围绕膜平面的法线快速旋转（即τ R 10− 5 S）。其次，磷酸基团和甘油CH 2 OP基团的受限内部运动与肌浆网磷脂形成的脂质体中发现的非常相似。校准实验表明，膜中所有（100±7%）的磷脂分子都可以在所观察到的光谱中解释。因此，基本上所有的磷脂分子在肌质网膜和重建的肌质网膜具有相同的运动在极性头基区中发现的模型双层膜。由于大部分磷脂分子（在四分之一和二分之一之间，取决于脂质与蛋白质的比例）直接围绕着钙泵蛋白，我们得出结论，钙泵蛋白不会干扰这些“边界层”脂质的运动。
Abstract 31 P-NMR spectra were obtained from oriented multilayer preparations of normal sarcoplasmic reticulum and reconstituted sarcoplasmic reticulum with lipid to protein ratios varying between 42: 1 and 110: 1. The dependence of the 31 P-NMR spectra on the alignment of the membranes with respect to the magnetic field was used to draw two conclusions about the motion of the phospholipid molecules that contribute to the observed spectra. First, the phosphate group and the two adjacent methylene groups are able to rapidly rotate (ie, τ R⪡⪡ 10− 5 S) around the normal to the plane of the membrane. Second, the restricted internal motion of the phosphate group and the glycerol CH 2 OP group is very similar to that found in liposomes formed from sarcoplasmic reticulum phospholipids. Calibration experiments showed that all (100±7%) of the phospholipid molecules in the membrane can be accounted for in the observed spectra. Thus, essentially all the phospholipid molecules in the sarcoplasmic reticulum and the reconstituted sarcoplasmic reticulum membranes have the same motion in the polar headgroup region as found in model bilayer membranes. Since a large fraction of the phospholipid molecules (between one-quarter and one-half, depending on the lipid to protein ratio) are immediately surrounding the calcium-pump protein, we conclude that the calcium-pump protein does not perturb the motion of these ‘boundary-layer’lipids.