thiol-activated haemolysins

(= oxygen-labile haemolysins)

Cytolytic bacterial exotoxins that act by binding to cholesterol in cell membranes and forming ring-like complexes that act as pores. SH-groups of these toxins must be in the reduced state for the toxin to function. Oxidation (to disulphide bridges) inactivates the toxin. Examples: tetanolysin, streptolysin O, q -toxin (perfringolysin), cereolysin.