[DNAase activity, a method of differentiating hospital strains of Salmonella typhimurium]

Measurements of DNAse activities in Salmonella typhimurium strains of various origins have demonstrated that hospital strains are characterized by the highest DNAse activity. This activity correlates with the presence of R-plasmids in the cells. High DNAse activity of hospital strains is a stable marker, and therefore may be used for intraspecies differentiation of S. typhimurium.