Listeriolysin O

Definition

Listeriolysin O is a pore-forming toxin produced by the bacterium Listeria monocytogenes. It plays a crucial role in the pathogen's ability to escape from phagosomes into the host cell cytoplasm.

5 Must Know Facts For Your Next Test

1. Listeriolysin O (LLO) is essential for Listeria monocytogenes to invade and survive within host cells.
2. LLO enables Listeria to escape from the phagosome before it fuses with lysosomes, thus avoiding degradation.
3. The optimal activity of LLO occurs at an acidic pH, which is typically found within phagosomes.
4. Mutations in the gene encoding LLO (hly gene) can significantly reduce the virulence of Listeria monocytogenes.
5. LLO also contributes to the inflammatory response during infection by facilitating bacterial dissemination.

Review Questions

Related terms

Phagosome:

A vesicle formed around a particle engulfed by a phagocyte via phagocytosis.

Listeria monocytogenes:

A Gram-positive bacterium that causes listeriosis, particularly affecting immunocompromised individuals and pregnant women.

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