title: Central role of the Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR) in sodium bioenergetics of Vibrio cholerae.
abstract: Vibrio cholerae is a Gram-negative bacterium that lives in brackish or sea water environments. Strains of V. cholerae carrying the pathogenicity islands infect the human gut and cause the fatal disease cholera. Vibrio cholerae maintains a Na(+) gradient at its cytoplasmic membrane that drives substrate uptake, motility, and efflux of antibiotics. Here, we summarize the major Na(+)-dependent transport processes and describe the central role of the Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR), a primary Na(+) pump, in maintaining a Na(+)-motive force. The Na(+)-NQR is a membrane protein complex with a mass of about 220 kDa that couples the exergonic oxidation of NADH to the transport of Na(+) across the cytoplasmic membrane. We describe the molecular architecture of this respiratory complex and summarize the findings how electron transport might be coupled to Na(+)-translocation. Moreover, recent advances in the determination of the three-dimensional structure of this complex are reported.
authors.forename: Julia
authors.initials: J
authors.lastname: Steuber
authors.forename: Petra
authors.initials: P
authors.lastname: Halang
authors.forename: Thomas
authors.initials: T
authors.lastname: Vorburger
authors.forename: Wojtek
authors.initials: W
authors.lastname: Steffen
authors.forename: Georg
authors.initials: G
authors.lastname: Vohl
authors.forename: Günter
authors.initials: G
authors.lastname: Fritz
mesh_terms: D001693:Biological Transport, Active; D002771:Cholera / Q000201:enzymology / Q000382:microbiology*; D018360:Crystallography, X-Ray; D004579:Electron Transport; D004734:Energy Metabolism; D006801:Humans; D008958:Models, Molecular; D011487:Protein Conformation; D011808:Quinone Reductases / Q000737:chemistry / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D014734:Vibrio cholerae / Q000201:enzymology* / Q000378:metabolism / Q000472:pathogenicity
chemical_list: D012964:Sodium; C041831:NADH dehydrogenase (quinone); D011808:Quinone Reductases