Shah D S, Thomas M B, Phillips S, Cisneros D A, Le Brun A P, Holt S A, Lakey J H
Orla Protein Technologies Ltd, Nanotechnology Centre, Newcastle upon Tyne NE1 7RU, UK.
Biochem Soc Trans. 2007 Jun;35(Pt 3):522-6. doi: 10.1042/BST0350522.
Membrane systems are based on several types of organization. First, amphiphilic lipids are able to create monolayer and bilayer structures which may be flat, vesicular or micellar. Into these structures membrane proteins can be inserted which use the membrane to provide signals for lateral and orientational organization. Furthermore, the proteins are the product of highly specific self-assembly otherwise known as folding, which mostly places individual atoms at precise places in three dimensions. These structures all have dimensions in the nanoscale, except for the size of membrane planes which may extend for millimetres in large liposomes or centimetres on planar surfaces such as monolayers at the air/water interface. Membrane systems can be assembled on to surfaces to create supported bilayers and these have uses in biosensors and in electrical measurements using modified ion channels. The supported systems also allow for measurements using spectroscopy, surface plasmon resonance and atomic force microscopy. By combining the roles of lipids and proteins, highly ordered and specific structures can be self-assembled in aqueous solution at the nanoscale.
膜系统基于几种类型的组织结构。首先,两亲性脂质能够形成单层和双层结构,这些结构可以是扁平的、囊泡状的或胶束状的。膜蛋白可以插入这些结构中,利用膜来提供侧向和定向组织的信号。此外,蛋白质是高度特异性自组装(即折叠)的产物,折叠大多将单个原子精确地置于三维空间中的特定位置。除了膜平面的尺寸外,这些结构的尺寸都在纳米尺度,膜平面在大脂质体中可能延伸数毫米,在平面表面(如空气/水界面的单分子层)上可能延伸数厘米。膜系统可以组装到表面上以形成支撑双层,这些支撑双层在生物传感器以及使用修饰离子通道的电学测量中有应用。支撑系统还允许使用光谱学、表面等离子体共振和原子力显微镜进行测量。通过结合脂质和蛋白质的作用,可以在纳米尺度的水溶液中自组装出高度有序和特定的结构。