Hydrolytic enzymes of Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius in relation to infection.

A collection of 518 'Streptococcus milleri' strains was tested for the presence of hydrolytic enzymes, and the results were related to the clinical significance of the strains. Ribonuclease activity was equally distributed among the three species while hyaluronidase activity was linked to Streptococcus intermedius and Streptococcus constellatus. Both enzymes were not significantly associated with infection-related strains. Deoxyribonuclease and chondroitin sulfatase activity tended to be present more frequently in Streptococcus intermedius and Streptococcus constellatus and was associated with infection-related strains (p < 0.001).