What is "amatoxin"

n. Any of a class of toxic peptides produced by several mushrooms of the genus ''Amanita'' and others

Amatoxin is the collective name of a subgroup of at least eight related toxic compounds found in several genera of poisonous mushrooms, most notably the death cap ( Amanita phalloides) and several other members of the genus Amanita, as well as some Conocybe, Galerina and Lepiota mushroom species. Amatoxins are lethal in even small doses. Unlike many ingested poisons they are not destroyed by heat so cooking the poisonous mushrooms does not diminish their lethality which can be as little as eating half a mushroom.