title: Protein-protein association and cellular localization of four essential gene products encoded by tellurite resistance-conferring cluster "ter" from pathogenic Escherichia coli.
abstract: Gene cluster "ter" conferring high tellurite resistance has been identified in various pathogenic bacteria including Escherichia coli O157:H7. However, the precise mechanism as well as the molecular function of the respective gene products is unclear. Here we describe protein-protein association and localization analyses of four essential Ter proteins encoded by minimal resistance-conferring fragment (terBCDE) by means of recombinant expression. By using a two-plasmid complementation system we show that the overproduced single Ter proteins are not able to mediate tellurite resistance, but all Ter members play an irreplaceable role within the cluster. We identified several types of homotypic and heterotypic protein-protein associations among the Ter proteins by in vitro and in vivo pull-down assays and determined their cellular localization by cytosol/membrane fractionation. Our results strongly suggest that Ter proteins function involves their mutual association, which probably happens at the interface of the inner plasma membrane and the cytosol.
authors.affiliation: Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Mlynska dolina B2, 842 15, Bratislava, Slovakia.
authors.forename: Lenka
authors.initials: L
authors.lastname: Valkovicova
authors.forename: Silvia Minarikova
authors.initials: SM
authors.lastname: Vavrova
authors.forename: Jozef
authors.initials: J
authors.lastname: Mravec
authors.forename: Jozef
authors.initials: J
authors.lastname: Grones
authors.forename: Jan
authors.initials: J
authors.lastname: Turna
mesh_terms: D002498:Centrifugation; D024881:Drug Resistance, Bacterial; D019453:Escherichia coli O157 / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D020043:Genes, Essential; D005816:Genetic Complementation Test; D005810:Multigene Family; D011485:Protein Binding; D025941:Protein Interaction Mapping; D013691:Tellurium / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; C026660:tellurous acid; D013691:Tellurium