Whitfield Chris, Naismith James H
Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada.
Curr Opin Struct Biol. 2008 Aug;18(4):466-74. doi: 10.1016/j.sbi.2008.04.001. Epub 2008 May 19.
The cell envelope of Gram-negative bacteria protects the organism from environmental stresses, components of the innate immune response, and the actions of other antagonistic molecules. However, the complexity of the cell envelope dictated by these protective roles creates a significant challenge for assembly of the outer membrane. Extensive research has focused on the export and assembly of outer membrane proteins and there is continuing progress in this area. By contrast, knowledge of the export and assembly of complex glycoconjugates in the outer membrane has been limited until recently. New structural and biochemical information identifies an envelope-spanning molecular scaffold for the export of group 1 capsular polysaccharides and provides insight into a complex molecular machine.
革兰氏阴性菌的细胞包膜可保护机体免受环境压力、先天免疫反应成分以及其他拮抗分子作用的影响。然而,由这些保护作用所决定的细胞包膜的复杂性,给外膜的组装带来了重大挑战。大量研究聚焦于外膜蛋白的输出与组装,且该领域不断取得进展。相比之下,直到最近,人们对外膜中复杂糖缀合物的输出与组装的了解还很有限。新的结构和生化信息确定了一种跨包膜的分子支架,用于1型荚膜多糖的输出,并为一种复杂的分子机器提供了深入了解。