title: First analysis of a bacterial collagen-binding protein with collagen Toolkits: promiscuous binding of YadA to collagens may explain how YadA interferes with host processes.
abstract: The Yersinia adhesin YadA mediates the adhesion of the human enteropathogen Yersinia enterocolitica to collagens and other components of the extracellular matrix. Though YadA has been proposed to bind to a specific site in collagens, the exact binding determinants for YadA in native collagen have not previously been elucidated. We investigated the binding of YadA to collagen Toolkits, which are libraries of triple-helical peptides spanning the sequences of type II and III human collagens. YadA bound to many of them, in particular to peptides rich in hydroxyproline but with few charged residues. We were able to block the binding of YadA to collagen type IV with the triple-helical peptide (Pro-Hyp-Gly)(10), suggesting that the same site in YadA binds to triple-helical regions in network-forming collagens as well. We showed that a single Gly-Pro-Hyp triplet in a triple-helical peptide was sufficient to support YadA binding, but more than six triplets were required to form a tight YadA binding site. This is significantly longer than the case for eukaryotic collagen-binding proteins. YadA-expressing bacteria bound promiscuously to Toolkit peptides. Promiscuous binding could be advantageous for pathogenicity in Y. enterocolitica and, indeed, for other pathogenic bacteria. Many of the tightly binding peptides are also targets for eukaryotic collagen-binding proteins, and YadA was able to inhibit the interaction between selected Toolkit peptides and platelets. This leads to the intriguing possibility that YadA may interfere in vivo with host processes mediated by endogenous collagen-binding proteins.
authors.affiliation: Macromolecular X-ray Crystallography Group, Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, Helsinki, Finland.
authors.forename: Jack C
authors.initials: JC
authors.lastname: Leo
authors.forename: Heli
authors.initials: H
authors.lastname: Elovaara
authors.forename: Dominique
authors.initials: D
authors.lastname: Bihan
authors.forename: Nicholas
authors.initials: N
authors.lastname: Pugh
authors.forename: Sami K
authors.initials: SK
authors.lastname: Kilpinen
authors.forename: Nicolas
authors.initials: N
authors.lastname: Raynal
authors.forename: Mikael
authors.initials: M
authors.lastname: Skurnik
authors.forename: Richard W
authors.initials: RW
authors.lastname: Farndale
authors.forename: Adrian
authors.initials: A
authors.lastname: Goldman
mesh_terms: D018829:Adhesins, Bacterial / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D001422:Bacterial Adhesion / Q000502:physiology*; D001665:Binding Sites / Q000502:physiology; D002417:Cattle; D003094:Collagen / Q000235:genetics / Q000378:metabolism*; D024141:Collagen Type IV / Q000378:metabolism; D006801:Humans; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D019151:Peptide Library; D010973:Platelet Adhesiveness / Q000502:physiology; D015009:Yersinia Infections / Q000382:microbiology*; D015008:Yersinia enterocolitica / Q000502:physiology*
chemical_list: D018829:Adhesins, Bacterial; D024141:Collagen Type IV; D019151:Peptide Library; C064832:YadA protein, Yersinia; D003094:Collagen