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STUDIES ON THE PNEUMOCOCCUS : III. DISSOLUTION OF PNEUMOCOCCI IN PNEUMONIC CELLULAR MATERIAL AT VARYING HYDROGEN ION

F T Lord1, R N Nye

  • 1Research Laboratory of the Massachusetts General Hospital, Boston.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

Pneumococci bacteria dissolved in pneumonic lung material at specific pH levels, suggesting an enzymatic cause. Other Streptococcus species showed no such dissolution.

Area of Science:

  • Microbiology
  • Enzymology

Background:

  • Pneumococci are significant bacterial pathogens.
  • Understanding bacterial dissolution mechanisms is crucial for infection control.

Purpose of the Study:

  • To investigate the dissolution of pneumococci (Types I, II, and III) in pneumonic lung material.
  • To identify factors influencing pneumococcal dissolution, including pH and enzymatic activity.

Main Methods:

  • Mixing pneumococci with cellular material from pneumonic lung tissue.
  • Varying the pH of the experimental environment (6.95, 5.5, and 4.5).
  • Observing dissolution of pneumococci and comparing with other Streptococcus species.

Main Results:

  • Pneumococci Types I, II, and III underwent dissolution at pH 6.95 and 5.5.
  • No dissolution was observed at pH 4.5.
  • Streptococcus hemolyticus and Streptococcus viridans did not dissolve under the same conditions.

Conclusions:

  • Dissolution of pneumococci is pH-dependent.
  • An enzyme, potentially from the bacteria or lung material, likely causes pneumococcal dissolution.
  • This enzymatic activity is specific to pneumococci and not observed in other tested Streptococcus species.

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