Epsilon toxin (ETX) is produced by strains ofClostridium perfringensclas-sified as type B or type D. ETX belongs to the heptameric b-pore-forming toxins including aerolysin and Clostridium septicumalpha toxin, which are characterized by the formation of a pore through the plasma membrane of eukaryotic cells consisting in ab-barrel of 14 amphipaticbstrands.