Lipopolysaccharide transport to the cell surface: periplasmic transport and assembly into the outer membrane.

Philos Trans R Soc Lond B Biol Sci

Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA Department of Molecular and Cellular Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA

Published: October 2015

Gram-negative bacteria possess an outer membrane (OM) containing lipopolysaccharide (LPS). Proper assembly of the OM not only prevents certain antibiotics from entering the cell, but also allows others to be pumped out. To assemble this barrier, the seven-protein lipopolysaccharide transport (Lpt) system extracts LPS from the outer leaflet of the inner membrane (IM), transports it across the periplasm and inserts it selectively into the outer leaflet of the OM. As LPS is important, if not essential, in most Gram-negative bacteria, the LPS biosynthesis and biogenesis pathways are attractive targets in the development of new classes of antibiotics. The accompanying paper (Simpson BW, May JM, Sherman DJ, Kahne D, Ruiz N. 2015 Phil. Trans. R. Soc. B 370, 20150029. (doi:10.1098/rstb.2015.0029)) reviewed the biosynthesis of LPS and its extraction from the IM. This paper will trace its journey across the periplasm and insertion into the OM.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4632603PMC
http://dx.doi.org/10.1098/rstb.2015.0027DOI Listing

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