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Purification of a High Molecular Mass Protein in Streptococcus mutans
Published on: September 14, 2019
THE CONVERSION OF HEMOLYTIC STREPTOCOCCI TO NON-HEMOLYTIC FORMS
1Hospital of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Hemolytic streptococcus strains showed varying hemolysis based on oxygen levels. A non-hemolytic variant, developed through animal passage, could degrade hemolysin, potentially explaining Streptococcus haemolyticus to Streptococcus viridans transmutation.
Area of Science:
- Microbiology
- Bacteriology
- Streptococcus research
Background:
- Hemolytic streptococci exhibit variable hemolytic activity.
- Oxygen availability influences streptococcal hemolysis.
- Animal passage can alter bacterial characteristics.
Purpose of the Study:
- To investigate the hemolytic properties of Streptococcus strains under varying oxygen conditions.
- To characterize a non-hemolytic variant of hemolytic streptococcus.
- To explore the potential role of hemolysin degradation in bacterial transmutation.
Main Methods:
- Isolation and culturing of three Streptococcus strains from a single hemolytic source.
- Assessment of hemolytic activity on blood agar under aerobic and anaerobic conditions.
- Observation of hemolysin degradation by a non-hemolytic variant.
Main Results:
- Three distinct hemolytic forms were isolated, with differential hemolysis on blood agar.
- All three forms exhibited hemolysis under anaerobic conditions.
- A non-hemolytic variant, developed via mouse passage, degraded its own hemolysin and that of other strains under aerobic conditions.
Conclusions:
- Oxygen tension significantly impacts Streptococcus hemolytic activity.
- A non-hemolytic Streptococcus variant possesses hemolysin-degrading capabilities.
- These findings may elucidate the mechanism behind Streptococcus haemolyticus to Streptococcus viridans transmutation through animal passage.
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