Noinaj Nicholas, Rollauer Sarah E, Buchanan Susan K
Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, United States.
National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, United States.
Curr Opin Struct Biol. 2015 Apr;31:35-42. doi: 10.1016/j.sbi.2015.02.012. Epub 2015 Mar 19.
The outer membranes (OM) of Gram-negative bacteria contain a host of β-barrel outer membrane proteins (OMPs) which serve many functions for cell survival and virulence. The biogenesis of these OMPs is mediated by the β-barrel assembly machinery (BAM) complex which is composed of five components including the essential core component called BamA that mediates the insertase function within the OM. The crystal structure of BamA has recently been reported from three different species, including a full-length structure from Neisseria gonorrhoeae. Mutagenesis and functional studies identified several conformational changes within BamA that are required for function, providing a significant advancement towards unraveling exactly how BamA and the BAM complex are able to fold and insert new OMPs in the OM.
革兰氏阴性菌的外膜(OM)含有大量β-桶状外膜蛋白(OMP),这些蛋白对细胞存活和毒力起着多种作用。这些OMP的生物合成由β-桶状组装机器(BAM)复合体介导,该复合体由五个组分组成,包括称为BamA的必需核心组分,它介导外膜内的插入酶功能。最近报道了来自三种不同物种的BamA晶体结构,包括淋病奈瑟菌的全长结构。诱变和功能研究确定了BamA内几个功能所需的构象变化,这为准确揭示BamA和BAM复合体如何在OM中折叠和插入新的OMP取得了重大进展。