Faculty of Life Sciences, The University of Manchester, Oxford Road, Manchester, UK.
Trends Microbiol. 2011 Jan;19(1):40-8. doi: 10.1016/j.tim.2010.10.006. Epub 2010 Dec 3.
Gram-negative bacteria need to maintain the integrity of their outer membrane while also regulating the secretion of toxins and other macromolecules. A variety of dedicated outer membrane proteins (OMPs) facilitate this process. Recent structural work has shown that some of these proteins adopt classical β-barrel transmembrane structures and rely on structural changes within the barrel lumen to allow passage of substrate proteins. Other secretion systems have OMP components which use transmembrane α-helices and appear to function in a different way. Here we review a selection of recent structural studies which have major ramifications for our understanding of the passage of macromolecules across the outer membrane.
革兰氏阴性菌需要维持其外膜的完整性，同时调节毒素和其他大分子的分泌。各种专用的外膜蛋白（OMPs）促进了这一过程。最近的结构研究表明，其中一些蛋白质采用经典的β-桶跨膜结构，并依赖于桶腔内部的结构变化来允许底物蛋白通过。其他分泌系统的 OMP 组件使用跨膜α-螺旋，其功能似乎有所不同。在这里，我们回顾了一些最近的结构研究，这些研究对我们理解大分子穿过外膜的过程有重大影响。
