Outer membrane protein YadA of enteropathogenic yersiniae mediates specific binding to cellular but not plasma fibronectin

Abstract

The binding of bacteria or bacterial products to host proteins of tissue extracellular matrix may be a mechanism of tissue adherence. We investigated interactions of the plasmid-encoded outer membrane protein YadA, which confers pathogenic functions on enteropathogenic yersiniae, with fibronectin. Attachment of YadA-positive and YadA-negative recombinant Yersinia enterocolitica strains to cartilage-derived human cellular fibronectin and human plasma fibronectin in the solid phase revealed that YadA mediates binding of yersiniae to cellular fibronectin in a saturable, concentration-dependent manner. The interaction could be inhibited by an anti-YadA-specific anti-serum. An anti-beta 1-integrin antibody and the synthetic peptide G-R-G-D-S-P, representing the binding site for alpha 5 beta 1-integrin on fibronectin, did not block attachment of YadA-positive yersiniae to cellular fibronectin, indicating a binding site for YadA on cellular fibronectin independent of the R-G-D-S-containing site. By contrast, YadA failed to mediate binding to plasma fibronectin immobilized on nitrocellulose or plastic surfaces. These observations provide evidence for the hypothesis that the binding region for YadA in cellular fibronectin is not present in plasma fibronectin. This study is the first report on differential binding of bacteria to splicing variants of fibronectin. Further experiments might answer the question whether binding of YadA to cellular fibronectin contributes to the pathogenesis of yersiniae, both to the initial adhesion of the bacteria to the matrices of the host and to the arthritogenic potential of enteropathogenic yersiniae.

Fibronectin: a multidomain host adhesin targeted by bacterial fibronectin-binding proteins

“…Further study of YadA binding using human cellular fibronectin and human plasma fibronectin revealed that only the former bound YadA. The simplest explanation is that the YadAbinding site in fibronectin is not present in the plasma variant of this protein (Schulze-Koops et al, 1993). Now, YadA is a virulence factor of Y. enterocolitica, but is dispensable for the virulence of Y. pseudotuberculosis, and in wild-type Y. pestis, the yadA gene has a frameshift mutation silencing the gene.…”

Autotransporter proteins: novel targets at the bacterial cell surface

“…The second functional motif is two proline-rich regions; one lying immediately adjacent to the RGD motif and the other within the C-terminal region of the protein (Emsley et al, 1996). These sites may provide rapid (though weak), nonstoichiometric binding sites that are functionally (Roggenkamp et al, 1996) Extracellular matrix proteins (Emody et al, 1989;Schulzekoops et al, 1992Schulzekoops et al, , 1993 Protects against complement and defensin lysis (Balligand et al, 1985;Pilz et al, 1992;Flugel et al, 1994) Autoaggregation (Skurnik et al, 1984) important (Williamson, 1994). Other autotransporter proteins also possess loops extending from the predicted b-helix structure, which may incorporate uncharacterized functional motifs.…”

Hydrophobic domains affect the collagen‐binding specificity and surface polymerization as well as the virulence potential of the YadA protein of Yersinia enterocolitica

“…YadA mediates bacterial adherence to various types of collagen (Embdy et al, 1989;Schulze-Koops et al, 1992) as well as to fibronectin (Tertti et ai, 1992;Schulze-Koops et al, 1993). We assessed the E. coli C600 strains (expressing the wild-type YadAveos and YadAYeo3 .\83-io4) for adherence to various proteins of the extracellular matrix as well as to reconstituted basement membrane immobilized on glass.…”