Lack of correlation between the presence of plasmids and fimbriae in Yersinia enterocolitica and Yersinia pseudotuberculosis.

Thirty-nine strains of Yersinia enterocolitica and 10 strains of Yersinia pseudotuberculosis were studied for the presence of fimbriae, plasmids and two plasmid associated phenotypic expressions, autoagglutination and Ca2+ dependent growth at 37 degrees C. All of the strains studied became fimbriated, which was confirmed by electron microscopy and haemagglutination tests. Fimbriation was not correlated with the presence or absence of plasmids.