Charybdotoxin

Charybdotoxin (CTX) is a 37 amino acid neurotoxin from the venom of the scorpion Leiurus quinquestriatus hebraeus (Deathstalker) that blocks calcium-activated potassium channels. This blockade causes hyperexcitability of the nervous system. It is a close homologue of agitoxin and both toxins come from Leiurus quinquestriatus hebraeus.