Purification and characterization of P fimbriae from an Escherichia coli strain isolated from a septicemic turkey

Abstract

A pap+ Escherichia coli isolate from a turkey with colisepticemia expressed P fimbriae with a major subunit of an apparent molecular mass of 18 kDa which reacted with anti-F11 serum. This fimbriae was purified and polyclonal antiserum was produced in rabbits. The N-terminal amino acid sequence of the major fimbrial subunit of the avian P fimbriae was identical to that of F11. On immunoblotting, the antiserum against the avian P fimbriae strongly reacted with the major subunit of the homologous fimbriae, with F11, and with F165(1) fimbriae. Some antigenic determinants on the major subunits of F13, F7(1), and F7(2) fimbriae, with a stronger reaction against F13 fimbriae, were also recognized. The F11 antiserum reacted similarly to the antiserum against avian P fimbriae although cross-reactions against F13, F7(1), and F7(2) fimbriae were equivalent. In a competitive enzyme-linked immunosorbent assay, serological differences were observed between the purified avian P fimbriae and F11. Thus, the avian P fimbriae is closely related but not identical to F11 fimbriae which are associated with E. coli isolated from human urinary tract infection.