Periplasmic export machines for outer membrane assembly
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Updated: Jul 5, 2026

Directed Protein Packaging within Outer Membrane Vesicles from Escherichia coli: Design, Production and Purification
Published on: November 16, 2016
Chris Whitfield1, James H Naismith
1Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada. cwhitfie@uoguelph.ca
Abstract:
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.
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