Molecular cloning of the fimbrial subunit gene from a benign type B isolate ofBacteroides nodosus

The fimbrial subunit gene from the benign type BBacteroides nodosus isolate AC/6 was cloned into theSphI site of the multicopy vector plasmid pUC19. FiveEscherichia coli recombinants that were positive in a colony immunoassay were shown, by Western transfer analysis, to produce an immunologically cross-reacting protein of identical molecular size to fimbrial subunits prepared fromB. nodosus AC/6. Restriction endonuclease analysis showed that 4 of the recombinant plasmids carried a 6.7 kbSphI fragment. Recloning experiments showed that the fimbrial subunit gene was located within a 2.5 kbEcoRI-SphI fragment and that there was aPstI site located within the structural gene or its regulatory region. These recombinant clones will prove useful for the construction of a multivalent recombinant vaccine for the control of ovine footrot.