Biomembrane Structure Unit, Biochemistry Dept., University of Oxford, Oxford, OX1 3QU, UK.
Curr Opin Chem Biol. 2011 Oct;15(5):690-5. doi: 10.1016/j.cbpa.2011.07.021. Epub 2011 Aug 19.
The plasma membrane functions as a semi-permeable barrier, defining the interior (or cytoplasm) of an individual cell. This highly dynamic and complex macromolecular assembly comprises predominantly lipids and proteins held together by entropic forces and provide the interface through which a cell interacts with its immediate environment. The extended sheet-like bilayer structure formed by the phospholipids is a highly adaptable platform whose structure and composition may be tuned to provide specialised functionality. Although a number of biophysical techniques including X-ray crystallography have been used to determine membrane protein structures, these methods are unable to replicate and accommodate the complexity and diversity of natural membranes. Solid state NMR (ssNMR) is a versatile method for structural biology and can be used to provide new insights into the structures of membrane components and their mutual interactions. The extensive variety of sample forms amenable for study by ssNMR, allows data to be collected from proteins in conditions that more faithfully resemble those of native environment, and therefore is much closer to a functional state.
细胞膜起到半透性屏障的作用,界定了单个细胞的内部(即细胞质)。这个高度动态和复杂的大分子组装体主要由脂质和蛋白质组成,它们通过熵力结合在一起,并提供了细胞与其周围环境相互作用的界面。由磷脂形成的伸展片状双层结构是一个高度适应性的平台,其结构和组成可以进行调整以提供特殊功能。尽管已经使用了包括 X 射线晶体学在内的多种生物物理技术来确定膜蛋白结构,但这些方法无法复制和适应天然膜的复杂性和多样性。固态 NMR(ssNMR)是一种用于结构生物学的多功能方法,可用于深入了解膜成分的结构及其相互作用。ssNMR 适用于研究的广泛的样本形式,允许从更真实地类似于天然环境条件下的蛋白质中收集数据,因此更接近功能状态。