Detection of Yersinia pestis and Y-pseudotuberculosis by PCR amplification of 16S rRNA and its genes

A method was developed for detecting causative agents of plague (Yersinia pestis) and pseudotuberculosis (Y. pseudotuberculosis) by PCR with specific primers complementary to the variable regions V1 (hairpin 6) and V3 (hairpin 18) of 168 rRNA. Hybridization of respective labeled DNA probes with various bacterial species showed that the V1 region is similar in six species of genus Yersinia, whereas the V3 region is identical only for Y. pestis and Y. pseudotuberculosis. The primers yielded selective amplification of Y. pestis 16S rRNA fragment, in contrast to E. coli 168 rRNA. PCR on templates of partly purified nucleic acids from various strains of six Yersinia species demonstrated that only with Y. pestis and Y. pseudotuberculosis the primers directed synthesis of 399-bp rDNA. Restriction analysis of the PCR products confirmed that they originated from 16S rDNA, but failed to reveal differences between Y. pestis and Y. pseudotuberculosis. The specific test for 168 rRNA of these bacteria belonging probably to one phylogenetic taxon may be used for detection of plague and pseudotuberculosis.