Functional Variability of Type 1 Fimbriae of Escherichia coli

Type 1 fimbriae and the FimH-adhesins of E. coli differ in adhesive functions: those of a meningitis isolate IHE3034 mediate adhesion to collagens whereas those of an avirulent K-12 strain PC31 do not. Amino acid residue Alanine-62 in the FimH is critical for the collagen binding ability: substitution of Ala62 of IHE3034 FimH into serine abolishes collagen adhrence whereas substitution of Ser62 of PC31 FimH into alanine restores the binding.