Age and serotype dependent binding of K88 fimbriae to porcine intestinal receptors.
The porcine small intestine contains several polypeptides that could function as receptors for K88-positive Escherichia coli. The mucus fraction contained three proteins with molecular weights of 25, 35 and 60 kDa respectively, which showed a high affinity for K88-positive E. coli cells, whereas brush borders contained a 16 kDa protein and a set of proteins ranging from 40-70 kDa. Depending on the K88 serotype tested, differences in binding to these proteins were observed. In particular, E. coli cells carrying K88ad fimbriae exhibited only a rather weak binding to mucus proteins. The influence of age of the pig on the presence of K88 receptors was also investigated. One-week-old and 35-days-old post-weaning piglets were shown to contain K88 receptors in their mucus while these receptors were hardly detectable in the mucus of 6-month-old pigs. The presence of receptors in the brush border fraction was shown to be independent of age. The binding of K88 fimbriae to mucus proteins was blocked using a lectin of Euonymus europeaus which specifically recognizes the Gal alpha(1-3)Gal sequence, indicating that this disaccharide forms a significant part of the receptor structure.
Department of Molecular Microbiology, Faculty of Biology, Vrije Universiteit Amsterdam, The Netherlands.
P T
PT
Willemsen
F K
FK
de Graaf
D000375:Aging / Q000378:metabolism*; D000818:Animals; D001422:Bacterial Adhesion / Q000502:physiology; D001665:Binding Sites / Q000502:physiology; D004926:Escherichia coli / Q000145:classification / Q000472:pathogenicity*; D010861:Fimbriae, Bacterial / Q000502:physiology*; D006026:Glycoside Hydrolases; D015151:Immunoblotting; D007413:Intestinal Mucosa / Q000382:microbiology*; D008871:Microvilli / Q000378:metabolism; D009093:Mucus / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000378:metabolism; D013552:Swine
D011506:Proteins; D006026:Glycoside Hydrolases