title: High-affinity binding of the basement membrane protein collagen type IV to the crystalline virulence surface protein array of Aeromonas salmonicida.
abstract: The surface of the fish pathogen Aeromonas salmonicida is covered by a paracrystalline array (the A-layer) which is a virulence factor for the organism. Quantification of the ability of A. salmonicida cells to bind collagen types I and IV in a 125I-radiolabelled liquid-phase assay showed that A-layer-positive cells bound high levels of collagen type IV, but significantly lower levels of collagen type I. Collagen type IV binding was confirmed using non-radiolabelled enzyme-linked immunosorbent assays. 125I-Collagen type IV binding was rapid, specific, saturable, high affinity, and essentially irreversible by unlabelled collagen type IV. The A-layer was responsible for collagen type IV binding because binding was inactivated by selective removal of the A-layer at pH 2.2, and neither isogenic A-layer-deficient A. salmonicida mutants nor strains of Aeromonas hydrophila possessing a morphologically similar paracrystalline array bound this basement membrane protein.
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, British Columbia, Canada.
authors.forename: T J
authors.initials: TJ
authors.lastname: Trust
authors.forename: M
authors.initials: M
authors.lastname: Kostrzynska
authors.forename: L
authors.initials: L
authors.lastname: Emödy
authors.forename: T
authors.initials: T
authors.lastname: Wadström
mesh_terms: D000333:Aeromonas / Q000378:metabolism* / Q000472:pathogenicity; D001422:Bacterial Adhesion / Q000502:physiology; D001426:Bacterial Proteins / Q000378:metabolism*; D001485:Basement Membrane / Q000378:metabolism; D001667:Binding, Competitive; D003094:Collagen / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D003094:Collagen