title: A novel packing arrangement of AcrB in the lipid bilayer membrane.
abstract: The central component AcrB of the Escherichia coli drug efflux complex AcrA-AcrB-TolC has been extensively investigated by X-ray crystallography of detergent-protein 3-D crystals. In these crystals, AcrB packs as trimers - the functional unit. We visualized the AcrB-AcrB interaction in its native environment by examining E. coli lipid reconstituted 2-D crystals, which were overwhelmingly formed by asymmetric trimers stabilized by strongly-interacting monomers from adjacent trimers. Most interestingly, we observed lattices formed by an arrangement of AcrB monomers distinct from that in traditional trimers. This hitherto unobserved packing, might play a role in the biogenesis of trimeric AcrB.
authors.affiliation: School of Biological Sciences, Private Bag 92019, University of Auckland, Auckland, New Zealand.
authors.forename: K
authors.initials: K
authors.lastname: Ly
authors.affiliation: School of Biological Sciences, Private Bag 92019, University of Auckland, Auckland, New Zealand.
authors.forename: J D
authors.initials: JD
authors.lastname: Bartho
authors.affiliation: Institute of Biochemistry, Max-von-Laue-Str. 9, Goethe-University Frankfurt am Main, Germany(1).
authors.forename: T
authors.initials: T
authors.lastname: Eicher
authors.affiliation: Institute of Biochemistry, Max-von-Laue-Str. 9, Goethe-University Frankfurt am Main, Germany(1).
authors.forename: K M
authors.initials: KM
authors.lastname: Pos
authors.affiliation: School of Biological Sciences, Private Bag 92019, University of Auckland, Auckland, New Zealand.
authors.forename: A K
authors.initials: AK
authors.lastname: Mitra
mesh_terms: D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D018360:Crystallography, X-Ray; D003902:Detergents / Q000494:pharmacology; D004926:Escherichia coli / Q000166:cytology / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008051:Lipid Bilayers / Q000378:metabolism*; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000737:chemistry* / Q000378:metabolism*; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D012492:Salts / Q000494:pharmacology; D013696:Temperature
chemical_list: D003902:Detergents; D029968:Escherichia coli Proteins; D008051:Lipid Bilayers; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D012492:Salts; C083496:AcrB protein, E coli
keywords: 2-D crystal; AcrB; Electron crystallography; Multi-drug efflux