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REVERSIBLE INACTIVATION OF THE SUBSTANCE INDUCING TRANSFORMATION OF PNEUMOCOCCAL TYPES
1United States Navy Research Unit at the Hospital of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Ascorbic acid inactivates Pneumococcus transforming substance through oxidation, a process influenced by copper ions and inhibited by sulfhydryl compounds. Activity can be restored, suggesting peroxide involvement in this oxidative inactivation.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- The transforming principle of Pneumococcus carries genetic information.
- Ascorbic acid (vitamin C) is a potent antioxidant.
- The interaction between ascorbic acid and biological molecules can lead to oxidative damage.
Purpose of the Study:
- To investigate the effect of ascorbic acid on the transforming substance of Pneumococcus Type III.
- To elucidate the mechanism of inactivation and potential restoration of activity.
- To explore the role of oxidation and related compounds in this process.
Main Methods:
- Treatment of Pneumococcus Type III transforming substance with ascorbic acid.
- Investigation of catalytic effects of cupric ions and inhibitory effects of sulfhydryl compounds.
- Assays to determine the restoration of transforming activity using glutathione and other agents.
- Testing the influence of oxygen exclusion and catalase.
- Comparison with other autoxidizable compounds like catechol and hydroquinone.
Main Results:
- Ascorbic acid inactivates Pneumococcus Type III transforming substance.
- This inactivation is catalyzed by cupric ions and prevented by sulfhydryl compounds.
- Transforming activity can be restored by sulfhydryl compounds like glutathione.
- Analogous compounds (catechol, hydroquinone) also affect the transforming substance.
- Inactivation is oxygen-dependent and mitigated by catalase, indicating peroxide formation.
Conclusions:
- The inactivation of Pneumococcus transforming substance by ascorbic acid is likely an oxidative process.
- Peroxide formation during autoxidation of ascorbic acid or related compounds is implicated.
- This finding has implications for understanding the stability of other biologically active molecules.
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