What is a well-known natural toxin found in mushrooms?

Amatoxins are a group of highly toxic compounds found in several species of mushrooms, most notably in the infamous Amanita phalloides, commonly known as the death cap mushroom. These toxins inhibit RNA polymerase II, which is critical for synthesizing messenger RNA in cells, leading to severe liver and kidney damage when ingested. The lethality of amatoxins makes them notorious in toxicology and mycology.

While psilocybin and mycotoxins are also associated with mushrooms, they do not represent natural toxins with the same level of danger as amatoxins. Psilocybin is a psychoactive compound used in certain mushrooms known as "magic mushrooms," which can alter perception and mood but is not typically classified as a toxin in the harmful sense. Mycotoxins, on the other hand, are toxic compounds produced by fungi that can contaminate various food sources, but they are broad and not specifically tied to mushrooms in the same direct threat way that amatoxins are.

Serotonin is a neurotransmitter found in the nervous system and is not a toxin. It is involved in regulating mood and other functions, but it does not demonstrate the toxic properties associated with amanita species that contain amatoxins. Thus,