膜融合を利用したバクテリオロドプシンの結晶化法 A 3D Crystal of Bacteriorhodopsin Obtained by Successive Fusion of the Vesicular Assemblies
Bacteriorhodopsin, the sole protein in the purple membrane of <I>Halobacterium salinarium</I>, functions as a light-driven proton pump. To obtain it's three-dimensional crystal, we have developed a new crystallization method which does not involve any step of complete destruction of the membrane. First, purple membrane was incubated at high temperature with neutral detergent and ammonium sulfate so that the membrane was converted into uniformly sized spherical vesicles. Then the vesicles were condensed at low temperature, where fusion of the vesicles produced a hexagonal crystal which is made up of planar membranes. Structural analysis showed that the trimeric structure of bacteriorhodopsin was retained in the crystal. The native lipid bound to a specific site in the protein was suggested to play an important role in maintaining the higher-order structure of the membrane.
日本結晶学会誌 42(2), 171-175, 2000-04-30
The Crystallographic Society of Japan