Gamma-Amanitin

"gamma"-Amanitin or γ-amanitin is a cyclic peptide of eight amino acids. It is an amatoxin, a group of toxins isolated from and found in several members of the mushroom genus "Amanita", one being the death cap ("Amanita phalloides") as well as the destroying angel, a complex of similar species, principally "A. virosa" and "A. bisporigera". The compound is highly toxic, inhibits RNA polymerase II, disrupts synthesis of mRNA, and can be fatal.