Asymmetric structure of the purple membrane.
Asymmetric structure of the purple membrane.
复制标题
紫色膜的不对称结构。
作者：
A. Blaurock;G. I. King
有功能和结构的证据表明，细菌视紫红质是不对称的定向跨越盐生盐杆菌的紫色膜。为了评估不对称的程度，从膜的X-射线衍射数据进行了分析，可能的电子密度分布。最近的一个理论预测，只有有限的几个配置文件是一致的连续衍射数据，并已发现两个可能的配置文件。这两个配置文件表明，蛋白质分子跨越脂质双层膜。两个轮廓都是不对称的;在膜的一半中有比另一半中更多的脂质分子，并且细菌视紫红质分子显示出轻微的互补不对称。
There is both functional and structural evidence that bacteriorhodopsin is oriented asymmetrically across the purple membrane of Halobacterium halobium. To assess the degree of asymmetry, the x-ray diffraction data from the membrane have been analyzed for possible electron-density profiles. A recent theory predicts that only a limited number of profiles are consistent with the continuous diffraction data, and two possible profiles have been found. Both profiles indicate that the protein molecules span a lipid bilayer in the membrane. Both profiles are asymmetric; there are more lipid molecules in one half of the membrane than in the other, and the bacteriorhodopsin molecule shows a slight complementary asymmetry.