A toadstool toxin that spurs convulsions, nausea, impaired speech and muscle stiffness — and has led to several deaths in Japan in recent years — has been isolated and identified by a team of scientists. The small molecule is familiar to synthetic chemists but had never been isolated from a natural source, researchers report online May 24 in Nature Chemical Biology.
Acute poisoning that leads to a breakdown of skeletal muscle tissue — a syndrome known as rhabdomyolysis — is not often caused by a mushroom and is quite different from the effects of toxins produced by Amanita species, says Petteri Nieminen, a specialist in physiology and toxicology at the University of Joensuu in Finland. Amanita mushrooms, including the notorious death cap and death angel, bear the toxins that are responsible for more than 90 percent of mushroom-caused fatalities.
The toxic nature of Russula subnigricans, the species addressed in the new study, has been on the margins of mushroom research, Nieminen said. The new work “might bring this type of poisoning more to the foreground of mushroom studies,” he says. “That would be a nice thing.” Many fungi that produce toxins also produce beneficial compounds that warrant investigation as therapeutics, Nieminen notes.