The salting-out test to identify virulent Yersinia pseudotuberculosis

A total of 54 strains including 8 serotypes of Yersinia pseudotuberculosis were examined to find out about their cell surface hydrophobicity and virulence plasmid-associated properties. All the strains which aggregated in 0.9% saline expressed the properties of calcium-dependent growth and autoagglutination. However, the hydrophilic strains did not possess virulence plasmid-associated properties. The above results suggest that the salting-out test with 0.9% saline could be an effective measure to differentiate the virulence plasmid-carrying strains of Y. pseudotuberculosis from those of plasmidless virulence.