title: Oligomeric behavior of the RND transporters CusA and AcrB in micellar solution of detergent.
abstract: We have used analytical ultracentrifugation to explore the oligomeric states of AcrB and CusA in micellar solution of detergent. These two proteins belong to the resistance, nodulation and cell division (RND) family of efflux proteins that are involved in multiple drug and heavy metal resistance. Only the structure of AcrB has been determined so far. Although functional RND proteins should assemble as trimers as AcrB does, both AcrB and CusA form a mixture of quaternary structures (from monomer to heavy oligomer) in detergent solution. The distribution of the oligomeric states was studied as a function of different parameters: nature and concentration of the detergent, ionic strength, pH, protein concentration. This pseudo-heterogeneity does not hamper the crystallization of AcrB as a homotrimer.
authors.affiliation: Laboratoire des Protéines Membranaires, Institut de Biologie Structurale, Jean-Pierre Ebel, UMR 5075 CNRS-CEA-UJF, 41, rue Jules Horowitz, 38027 Grenoble Cedex, France. david.stroebel@ens.fr <david.stroebel@ens.fr>
authors.forename: David
authors.initials: D
authors.lastname: Stroebel
authors.forename: Véronique
authors.initials: V
authors.lastname: Sendra
authors.forename: Dominique
authors.initials: D
authors.lastname: Cannella
authors.forename: Kerstin
authors.initials: K
authors.lastname: Helbig
authors.forename: Dietrich H
authors.initials: DH
authors.lastname: Nies
authors.forename: Jacques
authors.initials: J
authors.lastname: Covès
mesh_terms: D003460:Crystallization; D003902:Detergents / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D026901:Membrane Transport Proteins / Q000737:chemistry*; D008823:Micelles; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000737:chemistry*; D011485:Protein Binding; D011487:Protein Conformation; D014461:Ultracentrifugation
chemical_list: D003902:Detergents; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D008823:Micelles; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C083496:AcrB protein, E coli