Epsilon toxin: A fascinating pore-forming toxin

Abstract

Epsilon toxin (ETX) is produced by strains of Clostridium perfringens classified as type B or type D. ETX belongs to the heptameric β-pore-forming toxins including aerolysin and Clostridium septicum alpha toxin, which are characterized by the formation of a pore through the plasma membrane of eukaryotic cells consisting in a β-barrel of 14 amphipatic β strands. By contrast to aerolysin and C. septicum alpha toxin, ETX is a much more potent toxin and is responsible for enterotoxemia in animals, mainly sheep. ETX induces perivascular edema in various tissues and accumulates in particular in the kidneys and brain, where it causes edema and necrotic lesions. ETX is able to pass through the blood-brain barrier and stimulate the release of glutamate, which accounts for the symptoms of nervous excitation observed in animal enterotoxemia. At the cellular level, ETX causes rapid swelling followed by cell death involving necrosis. The precise mode of action of ETX remains to be determined. ETX is a powerful toxin, however, it also represents a unique tool with which to vehicle drugs into the central nervous system or target glutamatergic neurons. Clostridium perfringensε-toxin is a potent lethal toxin, which is responsible for animal enterotoxemia. It is structurally related to aerolysin and Clostridium septicumα-toxin. These toxins heptamerize, form pores through the plasma membrane, and induce cell necrosis, ε-toxin being the most potent. ε-toxin accumulates in the kidneys, passes the blood brain barrier and stimulates the glutamate release © 2011 The Author Journal compilation © 2011 FEBS.