ADHESION OF BOVINE ENTEROTOXIGENIC ESCHERICHIA-COLI (ETEC) BY TYPE 1-LIKE FIMBRIAE

Enterotoxigenic Escherichia coli (STa+) strains were isolated from adu lt bovine with diarrhea. These strains did not express any known ETEC specific adhesins. Although hemagglutination with rat and sheep erythr ocytes was observed in the presence of D-mannose (MRHA), these strains also showed mannose-sensitive hemagglutination (MSHA) with guinea-pig erythrocytes. Electron microscopic studies revealed the presence of f imbria-like structures (provisionally called ''F43ms'') on bacterial c ells grown at 37 degrees C but not on cells grown at 18 degrees C, How ever, it was observed by SDS-PAGE that the J-1 strain (F43ms(+)) produ ces a protein similar to F1 fimbriae, and this strain hybridized with a DNA probe for F1 fimbriae, Immunogold-labelling techniques indicated that a rabbit anti-serum is specific for F43ms fimbrial structures, b ut not for Type 1 fimbriae. The immunofluorescence test carried out wi th semipurified F43ms on bovine brush borders suggests that the fimbri a-like structures are responsible for the adhesion to bovine epithelia l cells.