
Full text loading...
The porcine brush border glycoproteins of 210 and 240 kDa, recognized by Escherichia coli K88ac fimbriae, contained O-linked oligosaccharides. The carbohydrate moieties were analysed by deglycosylation, lectin-binding and agglutination assays. Neuraminidase susceptibility of the 210 kDa receptor suggested that a sialoglycoprotein may act as receptor for the K88ac fimbriae. In contrast, K88ac-binding to the 210 and 240 kDa glycoproteins totally disappeared after fucosidase treatment, indicating the critical role of fucosyl residues at the receptor sites. Among the oligosaccharides extracted from these O-glycoproteins, K88ac fimbriae showed affinity for neutral sugar chains while sialylated species were not recognized. Our data suggest a possible role of the polypeptide backbone in the definition of receptor sites. Specific agglutination by K88ac-fimbriated E. coli of the erythrocytes of the hamster Mesocricetus auratus was inhibited by the anti-t peanut lectin and the lectins of Datura stramonium, Aleuria aurantia and Maackia amurensis. Hence, we propose that Galβ1-3GalNAc- and Fucα1-2Galβ1-3/4GIcNAc- are the main sequences mediating K88ac fimbrial binding. These structures were not detected in the non-adhesive piglet brush borders characterized by a high carbohydrate content. Additional oligosaccharides probably masked the underlying receptor structures.
Article metrics loading...
Full text loading...
References
Data & Media loading...