Interaction of a rat intestinal brush border membrane glycoprotein with type-1 fimbriae of Salmonella typhimurium.

Type-1 fimbriated Salmonella typhimurium was found to adhere to rat intestinal brush border membrane in a mannose sensitive manner. The maximum binding of the purified fimbriae observed with the rat illeal enterocytes was inhibited by 69.2% in presence of D-mannose. Brush border membrane from rat illeum was isolated, delipidified, solubilised and fractionated by affinity chromatography on type-1 fimbriae coupled Sepharose CL 4B column. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of the material eluted from the column with D-mannose revealed a single band of molecular weight 60 kDa. The direct binding of this affinity eluted glycoprotein to the purified type-1 fimbriae was demonstrated by a modified Western blot experiment. Our findings suggest that the 60 kDa glycoprotein may serve as a receptor for the type-1 fimbriae in the rat intestinal brush border membrane and thereby may help in mediating bacterial adherence to the host epithelium.