Progresses on crystallization methodology of membrane proteins

Membrane proteins play crucial roles in substance transportation, energy transformation and signal transduction. Three dimensional structural determination of membrane protein is significantly important for its biological function study and rational drug design. The molecular structures of membrane proteins are mainly determined via X-ray single crystal diffraction technique, for which high quality membrane protein crystals are required. However, due to its amphipathicity, the membrane proteins are hard to crystallize, resulting in difficulties in the structural determination. In recent years, some methods (such as in surfo methods and in cubo methods) have been developed specifically for crystallizing membrane proteins. The progresses on crystallization methodology of membrane proteins are reviewed, and the prospective in this field are also discussed.