title: Outer membrane targeting of passenger proteins by the vacuolating cytotoxin autotransporter of Helicobacter pylori.
abstract: Helicobacter pylori produces a number of proteins associated with the outer membrane, including adhesins and the vacuolating cytotoxin. These proteins are supposed to integrate into the outer membrane by beta-barrel structures, characteristic of the family of autotransporter proteins. By using the SOMPES (shuttle vector-based outer membrane protein expression) system for outer membrane protein production, we were able to functionally express in H. pylori the cholera toxin B subunit genetically fused to the C-terminal VacA domain. We demonstrate that the fusion protein is translocated to the H. pylori outer membrane and that the CtxB domain is exposed on the H. pylori surface. Thus, we provide the first experimental evidence that the C-terminal beta-domain of VacA can transport a foreign passenger protein to the H. pylori surface and hence acts as a functional autotransporter.
authors.affiliation: Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Ludwig-Maximilians-Universität, Munich, Germany. schmitt@m3401.mpk.med.uni-muenchen.de
authors.forename: W
authors.initials: W
authors.lastname: Fischer
authors.forename: R
authors.initials: R
authors.lastname: Buhrdorf
authors.forename: E
authors.initials: E
authors.lastname: Gerland
authors.forename: R
authors.initials: R
authors.lastname: Haas
mesh_terms: D000595:Amino Acid Sequence; D019677:Artificial Gene Fusion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002772:Cholera Toxin / Q000235:genetics / Q000378:metabolism*; D003603:Cytotoxins / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism; D014617:Vacuoles / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D002352:Carrier Proteins; D003603:Cytotoxins; D011993:Recombinant Fusion Proteins; C074689:VacA protein, Helicobacter pylori; D002772:Cholera Toxin; D014357:Trypsin