The Lipopolysaccharide Export Pathway in Escherichia coli: Structure, Organization and Regulated Assembly of the Lpt Machinery
نویسندگان
چکیده
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.
منابع مشابه
The Escherichia coli Lpt transenvelope protein complex for lipopolysaccharide export is assembled via conserved structurally homologous domains.
Lipopolysaccharide is a major glycolipid component in the outer leaflet of the outer membrane (OM), a peculiar permeability barrier of Gram-negative bacteria that prevents many toxic compounds from entering the cell. Lipopolysaccharide transport (Lpt) across the periplasmic space and its assembly at the Escherichia coli cell surface are carried out by a transenvelope complex of seven essential ...
متن کاملThe LptA protein of Escherichia coli is a periplasmic lipid A-binding protein involved in the lipopolysaccharide export pathway.
The LptA protein of Escherichia coli has been implicated in the transport of lipopolysaccharide (LPS) from the inner membrane to the outer membrane. Here we provide evidence that LptA binds structurally diverse LPS substrates in vitro and demonstrate that it interacts specifically with the lipid A domain of LPS. These results are consistent with LptA playing a chaperone role in the transport of...
متن کاملStructure and Functional Analysis of LptC, a Conserved Membrane Protein Involved in the Lipopolysaccharide Export Pathway in Escherichia coli*
LptC is a conserved bitopic inner membrane protein from Escherichia coli involved in the export of lipopolysaccharide from its site of synthesis in the cytoplasmic membrane to the outer membrane. LptC forms a complex with the ATP-binding cassette transporter, LptBFG, which is thought to facilitate the extraction of lipopolysaccharide from the inner membrane and release it into a translocation p...
متن کاملEffects of ackA, pta and poxB inhibition by antisense RNA on acetate excretion and recombinant beta interferon expression in Escherichia coli
Introduction: Escherichia coli (E.coli) is one of the most widely used hosts for the production of recombinant proteins. The main problem in getting high product yields and productivity is the accumulation of acetic acid (acetate) as an unwanted metabolic by-product. In this study, an antisense-based strategy as a metabolic engineering approach was employed to hamper the acetate excretion probl...
متن کاملHyperimmune lipopolysaccharide antiserum mediated inhibition of the adherence of E. coli O157:H7 to HEP-2 cells and large intestine of mice
Escherichia coli O157:H7 is found in cattle farms and can live in the intestine of healthy cattle. Mostcases of human illnesses including nonbloody diarrhea, hemorrhagic colitis and hemolytic uremic syndromecan be traced, either directly or indirectly, to cattle. One strategy for reducing the risk of EnterohemorrhagicEscherichia coli (EHEC) infections in human is to reduce the prevalence of inf...
متن کامل