title: Biochemical and functional characterization of Helicobacter pylori vesicles.
abstract: Helicobacter pylori can cause peptic ulcer disease and/or gastric cancer. Adhesion of bacteria to the stomach mucosa is an important contributor to the vigour of infection and resulting virulence. H. pylori adheres primarily via binding of BabA adhesins to ABO/Lewis b (Leb) blood group antigens and the binding of SabA adhesins to sialyl-Lewis x/a (sLex/a) antigens. Similar to most Gram-negative bacteria, H. pylori continuously buds off vesicles and vesicles derived from pathogenic bacteria often include virulence-associated factors. Here we biochemically characterized highly purified H. pylori vesicles. Major protein and phospholipid components associated with the vesicles were identified with mass spectroscopy and nuclear magnetic resonance. A subset of virulence factors present was confirmed by immunoblots. Additional functional and biochemical analysis focused on the vesicle BabA and SabA adhesins and their respective interactions to human gastric epithelium. Vesicles exhibit heterogeneity in their protein composition, which were specifically studied in respect to the BabA adhesin. We also demonstrate that the oncoprotein, CagA, is associated with the surface of H. pylori vesicles. Thus, we have explored mechanisms for intimate H. pylori vesicle-host interactions and found that the vesicles carry effector-promoting properties that are important to disease development.
authors.affiliation: Department of Medical Biochemistry and Biophysics, Umeå University, SE-901 87 Umeå, Sweden.
authors.forename: Annelie
authors.initials: A
authors.lastname: Olofsson
authors.forename: Anna
authors.initials: A
authors.lastname: Vallström
authors.forename: Katja
authors.initials: K
authors.lastname: Petzold
authors.forename: Nicole
authors.initials: N
authors.lastname: Tegtmeyer
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schleucher
authors.forename: Sven
authors.initials: S
authors.lastname: Carlsson
authors.forename: Rainer
authors.initials: R
authors.lastname: Haas
authors.forename: Steffen
authors.initials: S
authors.lastname: Backert
authors.forename: Sun Nyunt
authors.initials: SN
authors.lastname: Wai
authors.forename: Gerhard
authors.initials: G
authors.lastname: Gröbner
authors.forename: Anna
authors.initials: A
authors.lastname: Arnqvist
mesh_terms: D018829:Adhesins, Bacterial / Q000378:metabolism; D000942:Antigens, Bacterial / Q000378:metabolism; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000302:isolation & purification*; D001426:Bacterial Proteins / Q000378:metabolism; D005753:Gastric Mucosa / Q000382:microbiology; D016480:Helicobacter pylori / Q000472:pathogenicity*; D006801:Humans; D010743:Phospholipids / Q000032:analysis; D046509:Tissue Culture Techniques; D037521:Virulence Factors / Q000302:isolation & purification*
chemical_list: D018829:Adhesins, Bacterial; D000942:Antigens, Bacterial; C400429:BabA protein, Helicobacter pylori; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D010743:Phospholipids; C500808:SabA protein, Helicobacter pylori; D037521:Virulence Factors; C080866:cagA protein, Helicobacter pylori