THE GAFD PROTEIN OF THE G (F-17) FIMBRIAL COMPLEX CONFERS ADHESIVENESS OF ESCHERICHIA-COLI TO LAMININ

Escherichia coli IHE11088(pRR-5) expressing the G (F17) fimbria adhere d to immobilized laminin as well as to reconstituted basement membrane s. No adhesion was seen with the plasmidless strain IHE11088 or with t he deletion derivative IHE11088(pHUB110), which expresses the G-fimbri al filament with a defective GafD lectin and tacks N-acetyl-D-glucosam ine-specific binding. Adhesion of IHE11088(pRR-5) to laminin and to re constituted basement membranes was specifically inhibited by N-acetyl- D-glucosamine, and adhesion was abolished after N-glycosidase F treatm ent of laminin. The results show that the GafD lectin binds to laminin carbohydrate and suggest a novel function for the F17 fimbria in bind ing to mammalian basement membranes.