Pneumolysin O

Definition

Pneumolysin O is a toxin produced by Streptococcus pneumoniae that can damage host cell membranes and disrupt immune responses. It plays a crucial role in the pathogenesis of pneumococcal diseases.

5 Must Know Facts For Your Next Test

1. Pneumolysin O is a pore-forming toxin that inserts into host cell membranes causing cell lysis.
2. It can inhibit the function of phagocytes, aiding in bacterial evasion from the immune system.
3. Pneumolysin O activates the classical complement pathway, contributing to inflammation and tissue damage.
4. The presence of Pneumolysin O is a key virulence factor in pneumococcal pneumonia and other related infections.
5. Vaccines targeting Pneumolysin O are being researched for their potential to prevent pneumococcal infections.

Review Questions

• What role does Pneumolysin O play in the pathogenesis of Streptococcus pneumoniae?
• How does Pneumolysin O affect the host's immune response?
• Why is Pneumolysin O considered a key virulence factor in pneumococcal diseases?

Related terms

Streptococcus pneumoniae: A Gram-positive bacterium responsible for many respiratory tract infections, including pneumonia.

Virulence Factors: Molecules produced by pathogens that contribute to their ability to cause disease.

Classical Complement Pathway: A part of the immune system that enhances the ability to clear microbes and damaged cells through opsonization and lysis.