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THE OCCURRENCE OF PORPHYRINS IN CULTURES OF C. DIPHTHERIAE.
1Department of Bacteriology, College of Physicians and Surgeons, Columbia University, New York.
The Journal of General Physiology
|October 30, 2009
Summary
Researchers discovered a novel iron and copper porphyrin compound in Corynebacterium diphtheriae cultures. This unique molecule, potentially derived from cytochrome, correlates with the bacteria's toxin production.
Area of Science:
- Biochemistry
- Microbiology
- Toxicology
Background:
- Porphyrins are crucial biological pigments involved in various cellular processes.
- The presence and function of porphyrins in Corynebacterium diphtheriae have not been fully elucidated.
- Cytochrome, a key component in cellular respiration, is a potential source of porphyrin compounds.
Purpose of the Study:
- To identify and characterize a novel porphyrin compound found in liquid cultures of Corynebacterium diphtheriae.
- To investigate the composition and properties of this newly discovered porphyrin.
- To explore the relationship between the porphyrin's concentration and the biological activity of the culture filtrate, including toxin production.
Main Methods:
- Cultivation of Corynebacterium diphtheriae in liquid media.
- Isolation and purification of the porphyrin compound from the culture filtrate.
- Spectroscopic analysis to determine the porphyrin's chemical structure and composition.
- Assessment of oxidation-reduction properties.
- Correlation analysis between porphyrin content and biological titer (toxin levels).
Main Results:
- A previously undescribed complex porphyrin was identified in C. diphtheriae cultures.
- This porphyrin contains both iron and copper, a unique characteristic not previously reported for porphyrin compounds.
- The compound exhibits oxidation-reduction changes.
- Porphyrin concentration was found to be directly proportional to the biological titer of the culture filtrate.
Conclusions:
- A novel iron-copper porphyrin exists in Corynebacterium diphtheriae, likely originating from cytochrome.
- This finding represents the first report of a porphyrin molecule containing both iron and copper.
- The study suggests a potential link between cytochrome, this novel porphyrin, and the production of diphtheria toxin.
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