🦠microbiology review

Theta (θ) toxin

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Theta (θ) toxin is a pore-forming cytolysin produced by Clostridium perfringens. It contributes to tissue destruction and systemic toxicity during infection.

5 Must Know Facts For Your Next Test

  1. Theta toxin is also known as perfringolysin O.
  2. It disrupts cell membranes by forming pores, leading to cell lysis.
  3. Theta toxin is oxygen-labile and functions optimally in anaerobic conditions.
  4. It can be detected using the Nagler reaction, which identifies lecithinase activity.
  5. Theta toxin plays a significant role in gas gangrene, a severe and rapidly spreading infection.

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