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THE MODE OF ACTION OF SULFANILAMIDE ON STREPTOCOCCUS. II
F P Gay1, A R Clark, J A Street
1Department of Bacteriology, College of Physicians and Surgeons, Columbia University, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Sulfanilamide inhibits streptococcus growth, often causing bacteriostasis rather than destruction. Its therapeutic action depends on environmental factors and enhances phagocytosis, but does not eliminate bacterial virulence.
Area of Science:
- Microbiology
- Pharmacology
- Immunology
Background:
- Therapeutic action of sulfanilamide on Streptococcus requires understanding multifactorial influences on bacterial growth.
- Previous studies often oversimplified by examining single variables, neglecting their interrelationships.
Purpose of the Study:
- To comprehensively analyze factors affecting sulfanilamide's action on Streptococcus.
- To investigate the relationship between these factors and the drug's efficacy.
- To elucidate the mechanism of sulfanilamide's therapeutic effect in vivo and in vitro.
Main Methods:
- Experimental analysis of growth conditions (in vitro and in vivo) for Streptococcus in the presence of sulfanilamide.
- Assessment of bacteriostasis, sterilization, and bacterial virulence under varying conditions.
- Evaluation of phagocytosis enhancement by immune cells (polymorphonuclear and mononuclear) in response to sulfanilamide treatment.
- Investigation of sulfanilamide's effect on hemotoxin, leucocidin, and fibrinolysin production.
- Comparative analysis with other antimicrobial agents like arsenicals, acriflavine, and gentian violet.
Main Results:
- Sulfanilamide typically induces bacteriostasis, not complete bacterial destruction, in favorable growth media.
- Sterilization of cultures can occur in poor or inhibitory media.
- Enhanced phagocytosis by immune cells is observed when sulfanilamide is used therapeutically or with inhibited bacteria.
- Sulfanilamide temporarily inhibits hemotoxin formation but does not neutralize existing hemotoxin.
- The drug does not impair Streptococcus's innate virulence or significantly affect leucocidin/fibrinolysin production.
- Unlike other agents, Streptococcus does not adsorb or diminish sulfanilamide, nor does it increase susceptibility to other bactericidal substances.
Conclusions:
- Sulfanilamide's efficacy is highly dependent on environmental conditions and host defenses, particularly phagocytosis.
- The drug modulates bacterial growth and host immune response rather than directly sterilizing the infection.
- Sulfanilamide's unique interaction with Streptococcus differentiates it from other antimicrobial drugs.
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