Solid state NMR strategy for characterizing native membrane protein structures.
Solid state NMR strategy for characterizing native membrane protein structures.
复制标题
DOI：
10.1021/ar3003442
复制
发表时间：
2013-09-17
影响因子：
18.3
通讯作者：
CROSS, TIMOTHY A.
中科院分区：
文献类型：
--
作者：
Murray, Dylan T.;DAS, NABANITA;CROSS, TIMOTHY A.
与水溶性蛋白质不同，螺旋跨膜蛋白的结构依赖于非常复杂的环境。这些蛋白质位于戏剧性的电和化学梯度的中间，并且经常受到横向压力分布，序参数，介电常数和其他性质的变化。固态NMR是一系列可以在这种环境中表征高分辨率膜蛋白结构的工具。事实上，先前的工作已经表明，这种复杂的环境显着影响跨膜蛋白质的结构。因此，在与天然环境非常相似的条件下表征这些结构是很重要的。研究人员使用了两种方法通过固态NMR光谱获得蛋白质结构限制。更传统的方法使用魔角样品旋转来产生各向同性化学位移，很像溶液NMR。与溶液NMR一样，研究人员可以分析主链化学位移以获得扭转约束。他们还可以检查附近原子之间的核自旋相互作用，以获得原子位置之间的距离。不幸的是，对于膜蛋白在脂质preparations，光谱分辨率是不够的，以获得完整的共振assignments.Researchers开发了另一种方法，从膜蛋白获得结构的限制：使用均匀取向的脂质双层，这提供了一种方法，获得高分辨率的取向约束。当双层相对于NMR光谱仪的磁场对齐时，研究人员可以获得取向约束，其中蛋白质中的原子位点相对于对齐轴受到约束。然而，这种方法不允许研究人员确定螺旋之间的相对堆积。通过结合这两种方法，我们可以利用从每种技术中获得的信息，以最大限度地减少挑战并最大限度地提高结构结果的质量。通过结合的距离，扭转和取向的限制，我们可以表征高分辨率的膜蛋白质结构在天然的脂质双层环境。
Unlike water soluble proteins, the structures of helicaltransmembrane proteins depend on a very complex environment. These proteins sit in the midst of dramatic electrical and chemical gradients and are often subject to variations in the lateral pressure profile, order parameters, dielectric constant, and other properties. Solid state NMR is a collection of tools that can characterize high resolution membrane protein structure in this environment. Indeed, prior work has shown that this complex environment significantly influences transmembrane protein structure. Therefore, it is important to characterize such structures under conditions that closely resemble its native environment.Researchers have used two approaches to gain protein structural restraints via solid state NMR spectroscopy. The more traditional approach uses magic angle sample spinning to generate isotropic chemical shifts, much like solution NMR. As with solution NMR, researchers can analyze the backbone chemical shifts to obtain torsional restraints. They can also examine nuclear spin interactions between nearby atoms to obtain distances between atomic sites. Unfortunately, for membrane proteins in lipid preparations, the spectral resolution is not adequate to obtain complete resonance assignments.Researchers have developed another approach for gaining structural restraints from membrane proteins: the use of uniformly oriented lipid bilayers, which provides a method for obtaining high resolution orientational restraints. When the bilayers are aligned with respect to the magnetic field of the NMR spectrometer, researchers can obtain orientational restraints in which atomic sites in the protein are restrained relative to the alignment axis. However, this approach does not allow researchers to determine the relative packing between helices.By combining the two approaches, we can take advantage of the information acquired from each technique to minimize the challenges and maximize the quality of the structural results. By combining the distance, torsional, and orientational restraints, we can characterize high resolution membrane protein structure in native-like lipid bilayer environments.
登录
查看更多内容
影响因子：
3.4
作者：
Javadpour, MM;Eilers, M;Smith, SO
通讯作者：
Smith, SO
影响因子：
3.4
作者：
MOLL, F;CROSS, TA
通讯作者：
CROSS, TA
影响因子：
5.6
作者：
CROSS, TA;OPELLA, SJ
通讯作者：
OPELLA, SJ
影响因子：
3.7
作者：
HOLSINGER, LJ;LAMB, RA
通讯作者：
LAMB, RA
影响因子：
8
作者：
Duong-Ly, KC;Nanda, V;Howard, KP
通讯作者：
Howard, KP