A total of 54 strains including 8 serotypes of Yersinia pseudotubercul
osis were examined to find out about their cell surface hydrophobicity
and virulence plasmid-associated properties. Alt the strains which ag
gregated 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 su
ggest 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 avirulence.