Patent ID: 7163820

Claim:
A process for producing a nontoxic, fimbria producing Escherichia coli strain, which comprises the steps of: a) abolishing by genetic intervention the enterotoxin-producing ability of a wild pathogenic, enterotoxigenic Escherichia coli strain (Ec2173, O147:K+, NM, STa, STb, F18ac, Hly) originally adapted to producing enterotoxins and F18ac fimbria while retaining the ability of the strain to produce an F18ac fimbria; b) introducing an F4 plasmid into the strain by electroporation, conjugation, or transformation to produce a further surface adhesion fimbria (F4ac); and c) culturing the Escherichia coli strain (NBI/36-9) containing the plasmids for production of both F4ac and F18ac fimbria.