Streptolysins

Definition

Streptolysins are hemolytic exotoxins produced by Streptococcus bacteria that can destroy red and white blood cells. They play a significant role in the pathogenicity of streptococcal infections.

5 Must Know Facts For Your Next Test

1. There are two main types of streptolysins: streptolysin O (SLO) and streptolysin S (SLS).
2. Streptolysin O is oxygen-labile, meaning it is inactivated by oxygen, while streptolysin S is oxygen-stable.
3. Streptolysin O can be detected in the laboratory using an ASO (antistreptolysin O) titer test, which helps diagnose recent streptococcal infections.
4. Both types of streptolysins contribute to the virulence of Streptococcus pyogenes by lysing host cells and evading immune responses.
5. Streptolysins can cause tissue damage, contributing to conditions like pharyngitis, impetigo, and necrotizing fasciitis.

Review Questions

Related terms

Exotoxin: A toxin released by a bacterial cell into its surroundings.

Hemolysis:

The destruction of red blood cells leading to the release of hemoglobin.

Virulence Factor: A molecule produced by a pathogen that contributes to its ability to cause disease.