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Toxinogenic potential of Proteus mirabilis strains
Zentralblatt Fur Bakteriologie, Mikrobiologie, Und Hygiene. Series A, Medical Microbiology, Infectious Diseases, Virology, Parasitology
|May 1, 1984
Summary
Proteus mirabilis bacterial components trigger distinct skin reactions, with different fractions responsible for rapid and delayed responses. Further analysis revealed specific activities within these fractions, indicating complex antigenic properties.
Area of Science:
- Microbiology
- Immunology
- Toxicology
Background:
- Proteus mirabilis is a Gram-negative bacterium known to cause various infections.
- Understanding the pathogenic mechanisms and immune responses elicited by P. mirabilis is crucial for developing effective treatments.
Purpose of the Study:
- To investigate the biological activities of Proteus mirabilis live cultures and their filtrates in inducing skin reactions.
- To identify the specific fractions responsible for rapid and delayed hypersensitivity responses.
- To characterize the nature of the active components within these fractions.
Main Methods:
- Live bacterial suspensions and concentrated culture filtrates of Proteus mirabilis were used.
- Skin tests were performed to assess vascular permeability (rapid) and delayed reactions (hemorrhagic, dilatation, induration).
- Mice-foot edema tests and suckling mice tests for enterotoxin were conducted.
- Fractionation of culture filtrates based on molecular mass was performed, followed by biological activity assays.
Main Results:
- Both live P. mirabilis and its filtrates induced positive rapid and delayed skin tests, as well as footpad edema in mice.
- No thermostable enterotoxin was detected in suckling mice.
- Fraction 1 (MW > 100,000) was associated with delayed skin test activity, likely due to lipopolysaccharide.
- Fraction 2 (MW approx. 40,000) showed activity in the rapid skin test, along with cytotoxic and proteolytic properties.
- Both fractions contained active antigen substances with varying mobility and specificity.
Conclusions:
- Proteus mirabilis produces components that elicit both immediate and delayed inflammatory skin responses.
- Lipopolysaccharide is implicated in the delayed-type hypersensitivity reaction.
- A distinct fraction, likely proteinaceous, mediates the rapid vascular permeability response and exhibits cytotoxic/proteolytic activity.
- The study demonstrates the presence of multiple antigenic substances with differential biological activities in P. mirabilis.