Department of Biochemistry, University of Washington, Seattle, WA, USA.
Trends Biochem Sci. 2011 Aug;36(8):433-43. doi: 10.1016/j.tibs.2011.04.002. Epub 2011 May 11.
Secretins form megadalton bacterial-membrane channels in at least four sophisticated multiprotein systems that are crucial for translocation of proteins and assembled fibers across the outer membrane of many species of bacteria. Secretin subunits contain multiple domains, which interact with numerous other proteins, including pilotins, secretion-system partner proteins, and exoproteins. Our understanding of the structure of secretins is rapidly progressing, and it is now recognized that features common to all secretins include a cylindrical arrangement of 12-15 subunits, a large periplasmic vestibule with a wide opening at one end and a periplasmic gate at the other. Secretins might also play a key role in the biogenesis of their cognate secretion systems.
在至少四个复杂的多蛋白系统中，分泌蛋白形成巨大的细菌膜通道，这些系统对于许多种细菌的外膜蛋白和组装纤维的易位至关重要。分泌蛋白亚基包含多个结构域，与许多其他蛋白质相互作用，包括导肽、分泌系统伴侣蛋白和外分泌蛋白。我们对分泌蛋白结构的理解正在迅速发展，现在人们认识到，所有分泌蛋白的共同特征包括 12-15 个亚基的圆柱形排列、一个大的周质前庭，一端开口较宽，另一端有周质门。分泌蛋白在其同源分泌系统的生物发生中也可能发挥关键作用。
