Differential effects of the streptococcal fibronectin-binding protein, FBP54, on adhesion of group A streptococci to human buccal cells and HEp-2 tissue culture cells.
We have previously demonstrated that fibronectin mediates streptococcal adhesion to host cells and that streptococci interact primarily with the N-terminal domain of fibronectin. FBP54 is a 54-kDa protein from group A streptococci that binds fibronectin. In this report, we show that the N-terminal domain of fibronectin reacts with FBP54 and preferentially blocks streptococcal adhesion to buccal epithelial cells. FBP54 blocked adhesion to human buccal epithelial cells by 80% in a dose-related fashion. In contrast, FBP54 had little effect on adhesion of group A streptococci to HEp-2 tissue culture cells. The fibronectin-binding domain of FBP54 has been localized to the first 89 N-terminal residues of the protein. Experiments using affinity-purified antibodies to this region indicated that the N terminus of FBP54 is exposed on the surface of streptococci in a manner that can interact with immobilized receptors. Analysis of sera from patients with post-streptococcal glomerulonephritis and acute rheumatic fever indicated that FBP54 is expressed in vivo and is immunogenic in the human host. These data indicate that FBP54 is a streptococcal adhesin that is expressed in the human host and that preferentially mediates adhesion to certain types of human cells.
Courtney
H S
HS
Veterans Affairs Medical Center, Memphis, Tennessee 38104, USA.
Dale
J B
JB
Hasty
D I
DI
D018829:Adhesins, Bacterial / Q000276:immunology / Q000378:metabolism; D000595:Amino Acid Sequence; D000907:Antibodies, Bacterial / Q000097:blood; D001422:Bacterial Adhesion / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D001426:Bacterial Proteins; D001665:Binding Sites; D002352:Carrier Proteins; D002460:Cell Line; D002610:Cheek / Q000382:microbiology; D005353:Fibronectins / Q000378:metabolism; D005921:Glomerulonephritis / Q000276:immunology; D006801:Humans; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D012213:Rheumatic Fever / Q000276:immunology; D013290:Streptococcal Infections / Q000276:immunology; D013297:Streptococcus pyogenes / Q000378:metabolism* / Q000472:pathogenicity*
D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D005353:Fibronectins; D010446:Peptide Fragments; C078635:fibronectin-binding proteins, bacterial