IDENTIFICATION OF INVASIVE YERSINIA SPECIES USING OLIGONUCLEOTIDE PROBES

Oligonucleotide probes directed to the inv and ail invasion genes of Yersinia species were used to analyse yersiniae and non-yersiniae isolates by colony hybridization. The INV-3 probe, targeted to the inv gene of Yersinia pseudotuberculosis, hybridized with all 48 HeLa cell-invasive Y. pseudotuberculosis isolates examined; the PF-13 probe, specific for the ail gene of Yersinia enterocolitica, identified all invasive strains (36 of 52) of Y. enterocolitica tested. Neither probe hybridized with non-yersinia isolates or other Yersinia species. Southern analyses of restriction enzyme-digested genomic DNA confirmed the specificity of both probes. INV-3 hybridized with a 4·5 kilobase (kb) Bam HI fragment known to carry the inv gene in Y. pseudotuberculosis. PF-13 was specific for a 1·2 kb ClaI-Ava I fragment in Y. enterocolitica that carried the ail locus. Reactivity with either probe correlated closely with the ability of Y. pseudotuberculosis and Y. enterocolitica isolates to invade HeLa cells. © 1992.