title: The N-terminal half part of the oral streptococcal antigen I/IIf contains two distinct binding domains.
abstract: In order to investigate the binding properties of the antigen I/IIf from Streptococcus mutans, we analyzed the binding activity of five I/IIf derivatives expressed by I/IIf gene derivatives obtained by insertion of a kanamycin resistance marker. ELISA-derived binding assays showed that the derivatives containing both the N-terminal alanine-rich domain (A-region) and an A-region distal domain extending to amino-acid 766 were the most effective in binding biotinylated (Biot-) human salivary components (SAC) and Biot-epithelial cell membrane components. Sodium metaperiodate treatment of SAC inhibited these interactions, suggesting a binding specificity of the A-region distal domain for carbohydrate residues. All the I/IIf derivatives were found to bind Biot-type I collagen, Biot-laminin, Biot-keratin, and Biot-fibronectin, the derivatives containing the A-region but lacking the A-region distal domain exhibiting the highest binding levels. Sodium metaperiodate treatment of laminin had no effect on its binding to the derivatives, suggesting that carbohydrate residues of the ligand were not involved.
authors.affiliation: INSERM U424, Faculté de Chirurgie Dentaire, Strasbourg, France.
authors.forename: M A
authors.initials: MA
authors.lastname: Sciotti
authors.forename: I
authors.initials: I
authors.lastname: Yamodo
authors.forename: J P
authors.initials: JP
authors.lastname: Klein
authors.forename: J A
authors.initials: JA
authors.lastname: Ogier
mesh_terms: D000942:Antigens, Bacterial / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001422:Bacterial Adhesion / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001426:Bacterial Proteins; D050260:Carbohydrate Metabolism; D002462:Cell Membrane / Q000378:metabolism; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D006801:Humans; D007633:Keratins / Q000378:metabolism; D008024:Ligands; D008562:Membrane Glycoproteins; D010504:Periodic Acid / Q000494:pharmacology; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism; D012463:Saliva; D013295:Streptococcus mutans / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D016326:Extracellular Matrix Proteins; D008024:Ligands; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; C055764:S-layer proteins; D010504:Periodic Acid; D007633:Keratins; C009288:metaperiodate