Virulence plasmid (pYV)-associated susceptibility of Yersinia enterocolitica to chlorine and heavy metals

This study was aimed at elucidating the role of virulence plasmid (pYV) in the susceptibility of Yersinia enterocolitica to bactericidal agents such a s chlorine and heavy metals. Plasmid-bearing (pYV(+)) Y. enterocolitica was less susceptible to the antimicrobial action of chlorine and heavy metals compared with the isogenic plasmidless (pYV(-)) derivative. This difference was, however, observed only with bacteria cultured at 25 degreesC. pYV-ass ociated susceptibility apart, cells cultured at 37 degreesC were also found to be less susceptible to the antimicrobial action of these agents. The re sults indicate that the susceptibility of Y. enterocolitica to these agents was influenced both by the presence of the virulence plasmid and the tempe rature at which the cells were cultured.