Oyster mushroom fungus uses nerve gas to paralyse and eat tiny worms

The fungus that produces oyster mushrooms preys on small animals by releasing a paralyzing nerve agent called 3-octanone before it grows into a body.

To Alice Klein

Oyster mushrooms are delicious, but they have a dark side that many people don’t know about. The mushroom that produces oyster mushrooms uses nerve gas to paralyze and kill nematodes before sucking out the insides.

Oyster mushrooms are reproductive structures – or fruiting bodies – of fungi Pleurotus ostreatus. Since the 1980s, this fungus has been known to prey on nematodes.

Yen-Ping Hsueh and her colleagues at the Academia Sinica, a research institute in Taiwan, previously found that: P. ostreatus It contains a small lollipop-shaped structure that breaks open when the nematode presses its head against it. They found that, once ruptured, these structures released highly toxic gases into the nematode’s nervous system.

Researchers determined this by first inducing thousands of random gene mutations in the fungus. Caenorhabditis elegans.

The researchers then analyzed the contents of the lollipop structure of the unmutated fungus and found that it was packed with a volatile chemical called 3-octanone. When they exposed four different nematode species to this chemical, nerve and muscle cells throughout the body were flooded with large amounts of calcium ions, leading to rapid paralysis and death.

Xue calls this a “lollipop nerve gas” killing strategy.

A toxic lollipop structure is present on the mycelium. This is a long, branched structure that grows inside rotting wood and makes up the majority of fungi. Oyster mushrooms themselves are non-toxic, says Xue.

After the fungus kills its prey, its hypha grows on the nematode’s body and sucks out its contents. Rotting wood, on which the fungus primarily grows, lacks this nutrient, so it absorbs nitrogen. Shuwe says they might do this for the sake of

Nematodes are the most abundant animals in soil and are natural food for fungi, she says. Other fungi use a variety of tactics to capture nematode prey, such as sticky traps and nooses tightened around the neck.

the discovery that P. ostreatus Nematode feeding has led to some debate in the vegan community as to whether oyster mushrooms are truly a vegan food.

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