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Production, purification, and composition of staphylococcal alpha toxin
Journal of Bacteriology
|December 1, 1966
Summary
Researchers purified staphylococcal alpha toxin for characterization. The pure toxin was unstable and its specific cell membrane action remained unexplained, despite detailed chemical analysis.
Area of Science:
- Microbiology
- Immunology
- Biochemistry
Background:
- Staphylococcal alpha toxin is a key virulence factor.
- Characterization of the toxin is essential for understanding its mechanism of action and developing countermeasures.
Purpose of the Study:
- To produce and purify staphylococcal alpha toxin for detailed chemical and biological analysis.
- To investigate the toxin's stability, molecular properties, and amino acid composition.
Main Methods:
- Purification using acid-methanol precipitation, Sephadex G100 chromatography, and electrophoresis.
- Characterization via gel diffusion, immunoelectrophoresis, ultracentrifugation, and amino acid analysis.
- Assessment of stability at 0°C and investigation of potential stabilization methods.
Main Results:
- Obtained 12 mg/liter of pure alpha toxin with 25% yield.
- Pure toxin exhibited high instability (3-day half-life at 0°C) and could not be frozen.
- Determined molecular weight (approx. 30,000, lowest 21,200 ± 400), amino acid composition, and identified N-terminal amino acids (histidine, arginine).
Conclusions:
- Pure staphylococcal alpha toxin was successfully prepared and characterized.
- The toxin's instability and inability to be stabilized pose challenges for its study and application.
- The specific mechanism of action on cell membranes remains elusive, warranting further investigation.
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