A novel lectin-independent interaction of P fimbriae of Escherichia coli with immobilized fibronectin.
Binding of P fimbriae of uropathogenic Escherichia coli to purified human fibronectin and human placental type IV collagen was studied. In an enzyme immunoassay, purified P fimbriae bound strongly to immobilized intact fibronectin and to the aminoterminal 30-kDa fragment and the 120-140-kDa carboxyterminal fragments of fibronectin. Binding to the gelatin-binding 40-kDa fragment of fibronectin was considerably weaker. No binding to immobilized type IV collagen was seen. The interaction between P fimbriae and immobilized fibronectin was not inhibited by alpha-D-Gal-(1-4)-beta-D-Gal-1-O-Me, a receptor analog of P fimbriae. Moreover, a mutated P fimbria lacking the lectin activity behaved similarly in the adherence assays. Recombinant strains expressing the corresponding cloned fimbriae genes bound to immobilized fibronectin, but no binding to soluble 125I-labelled fibronectin was found. The results suggest that P fimbriae interact with immobilized fibronectin and that the binding mechanism does not involve the lectin activity of the fimbriae.
Westerlund
B
B
Department of General Microbiology, University of Helsinki, Finland.
Kuusela
P
P
Vartio
T
T
van Die
I
I
Korhonen
T K
TK
D001422:Bacterial Adhesion; D003094:Collagen / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism*; D010861:Fimbriae, Bacterial / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism; D006801:Humans; D037102:Lectins / Q000502:physiology; D010446:Peptide Fragments / Q000378:metabolism; D011485:Protein Binding; D011971:Receptors, Immunologic / Q000032:analysis*; D000509:alpha-Fetoproteins / Q000378:metabolism
D005353:Fibronectins; D006023:Glycoproteins; D037102:Lectins; D010446:Peptide Fragments; D011971:Receptors, Immunologic; D000509:alpha-Fetoproteins; C037872:pili, bacterial receptor; D003094:Collagen