The lipopolysaccharide export pathway in Escherichia coli: structure, organization and regulated assembly of the Lpt machinery.

Mar Drugs

Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy.

Published: February 2014

The bacterial outer membrane (OM) is a peculiar biological structure with a unique composition that contributes significantly to the fitness of Gram-negative bacteria in hostile environments. OM components are all synthesized in the cytosol and must, then, be transported efficiently across three compartments to the cell surface. Lipopolysaccharide (LPS) is a unique glycolipid that paves the outer leaflet of the OM. Transport of this complex molecule poses several problems to the cells due to its amphipatic nature. In this review, the multiprotein machinery devoted to LPS transport to the OM is discussed together with the challenges associated with this process and the solutions that cells have evolved to address the problem of LPS biogenesis.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3944529PMC
http://dx.doi.org/10.3390/md12021023DOI Listing

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