There are two antigenically distinct forms of this toxin, ET-A and ET-B, both with an evident protease activity certainly referable to the aminoacidic similarity with Staph. aureus serine protease and the replication of the most important three units sequence in its active site (replacing serine unit with glycine involve the loss of toxin activity). Exfoliatin toxin don’t seem to have proteolytic activity while the target of its unquestionable esterase activity causing epidermal splitting (Scalded Skin Syndrome) is already unknown despite the participation of a very specific protein dedicated to the integrity maintenance of the epidermis would be most likely.