Structure, topology, and dynamics of membrane peptides and proteins from solid-state NMR Spectroscopy
Structure, topology, and dynamics of membrane peptides and proteins from solid-state NMR Spectroscopy
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DOI：
10.1021/jp073652j
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发表时间：
2007-09-06
影响因子：
3.3
通讯作者：
Hong, Mei
中科院分区：
文献类型：
--
作者：
Hong, Mei
由于蛋白质 - 膜复合物的疏水性，膜蛋白的高分辨率结构极难确定。固态核磁共振波谱是一种独特且强大的原子分辨率探测手段，可用于研究这些重要生物分子的结构和动力学。本文总结了一些用于确定膜蛋白插入深度、取向、寡聚体结构以及长程（10 - 15埃）距离的新型固态核磁共振方法。现在可以使用几种互补的技术来确定膜蛋白的深度，这些技术在位点特异性、距离精度和对蛋白质的流动性要求方面各不相同。现在可以在有或没有宏观取向的情况下确定膜蛋白的取向，后者为固有曲率诱导蛋白的取向确定提供了一种新的替代方法。文中描述了对β - 折叠膜蛋白取向的新分析。现在可以使用一种F - 19自旋扩散技术来阐明膜肽组装体的四级结构，该技术可同时得出寡聚体数量以及高达15埃的分子间距离。最后，现在可以使用H - 1自旋测量高达约10埃的长程距离，精度优于1埃。这些方法在几种具有抗菌活性的β - 折叠膜肽以及两种α - 螺旋离子通道蛋白上得到了验证。最后，我们表明可以使用二维相关实验轻松研究膜蛋白几乎普遍存在的动力学。深入了解这些系统中的分子运动不仅能对这些膜蛋白的特定功能产生重要见解，还可用于其他目的，比如取向确定。
The high-resolution structure of membrane proteins is notoriously difficult to determine due to the hydrophobic nature of the protein-membrane complexes. Solid-state NMR spectroscopy is a unique and powerful atomic-resolution probe of the structure and dynamics of these important biological molecules. A number of new solid-state NMR methods for determining the depth of insertion, orientation, oligomeric structure, and long-range (10-15 angstrom) distances of membrane proteins are summarized. Membrane protein depths can now be determined using several complementary techniques with varying site-specificity, distance precision, and mobility requirement on the protein. Membrane protein orientation can now be determined with or without macroscopic alignment, the latter providing a novel alternative for orientation determination of intrinsically curvature-inducing proteins. The novel analyses of beta-sheet membrane protein orientation are described. The quaternary structure of membrane peptide assemblies can now be elucidated using a F-19 spin diffusion technique that simultaneously yields the oligomeric number and intermolecular distances up to 15 angstrom. Finally, long-range distances up to similar to 10 angstrom can now be measured using H-1 spins with an accuracy of better than 1 angstrom. These methods are demonstrated on several beta-sheet membrane peptides with antimicrobial activities and on two a-helical ion-channel proteins. Finally, we show that the nearly ubiquitous dynamics of membrane proteins can be readily examined using 2D correlation experiments. An intimate appreciation of molecular motion in these systems not only leads to important insights into the specific function of these membrane proteins but also may be exploited for other purposes such as orientation determination.