Beta-amanitin

Beta-amanitin or β-amanitin is a cyclic nonribosomal peptide of eight amino acids. It is an amatoxin, a group of toxins isolated from and found in in several members of the Amanita genus of mushrooms, one being the Death cap (Amanita phalloides) as well as the Destroying angel, a complex of similar species, principally A. virosa and A. bisporiga.