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Hydrolytic enzymes of Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius in relation

J A Jacobs1, E E Stobberingh

  • 1Department of Medical Microbiology, University Hospital of Maastricht, The Netherlands.

European Journal of Clinical Microbiology & Infectious Diseases : Official Publication of the European Society of Clinical Microbiology
|September 1, 1995
PubMed

Insights

Certain Streptococcus milleri group enzymes, like deoxyribonuclease and chondroitin sulfatase, are linked to infections. Hyaluronidase activity was found in specific species but not infection-related strains.

Area of Science:

  • Microbiology
  • Clinical Diagnostics
  • Bacteriology

Background:

  • The Streptococcus milleri group comprises several species, including Streptococcus intermedius, Streptococcus constellatus, and Streptococcus anginosus.
  • Understanding the enzymatic activities of these bacteria is crucial for their identification and clinical relevance.

Purpose of the Study:

  • To investigate the presence of specific hydrolytic enzymes in Streptococcus milleri group strains.
  • To correlate enzymatic activity with the clinical significance and species identification of these bacteria.

Main Methods:

  • Enzymatic assays were performed on 518 strains of the Streptococcus milleri group.
  • Activities of ribonuclease, hyaluronidase, deoxyribonuclease, and chondroitin sulfatase were assessed.
  • Results were statistically analyzed in relation to species and clinical significance.

Main Results:

  • Ribonuclease activity was uniformly distributed across all tested species.
  • Hyaluronidase activity was predominantly found in Streptococcus intermedius and Streptococcus constellatus.
  • Deoxyribonuclease and chondroitin sulfatase activities were significantly associated with Streptococcus intermedius and Streptococcus constellatus, and notably linked to infection-related strains (p < 0.001).

Conclusions:

  • Deoxyribonuclease and chondroitin sulfatase are potential markers for clinically significant Streptococcus intermedius and Streptococcus constellatus strains.
  • Hyaluronidase activity, while species-specific, did not correlate with infection.
  • Enzymatic profiling can aid in differentiating and assessing the pathogenic potential of Streptococcus milleri group bacteria.

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