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Plants talk. Sometimes in good ways, sometimes in bad ways; and when a kernel of corn sends a chemical signal to a seemingly harmless mold spore to begin producing the world’s most potent natural toxin – and the corn is then ingested – that conversation can turn deadly.

Marion Brodhagen, Western Washington University assistant professor of Biology, has received a $100,000 grant from the U.S. Department of Agriculture to research ways to interrupt this “chemical conversation” between the fungus and food source before it can get started.

“Fungi within the genus Aspergillus exist all around us, and usually we never even notice,” Brodhagen said. “But certain species can infect agricultural crops such as peanuts, corn, millet, and sorghum, where they produce an incredibly potent poison called aflatoxin. When they sense a particular chemical signal from the seeds they grow on, these fungi ‘switch on’ and begin to produce this toxin. What we’re trying to do is understand the signaling process, so we can find ways to either stop the communication from starting, or interrupt it before it can finish.”

Ingestion of highly contaminated foods is deadly to people and animals, and long-term exposure to lower levels can cause potentially deadly illnesses such as hepatitis. Alfatoxin poisoning is especially prevalent in developing countries worldwide. The fungus thrives in warm climates such as in Africa and India; outbreaks there have killed hundreds, and because aflatoxin is a known cancer-causing agent, it has caused spikes in the local cancer rates as well. Here in the United States, the Food and Drug Administration enforces rigorous screening for aflatoxin, rejecting samples that test positive for having more than 20 parts per billion affected (to visualize 20 ppb, think of a half-teaspoon of food coloring in a railroad tanker full of water).

“It doesn’t take much aflatoxin to make quite a lot of people sick,” Brodhagen said. “We’re also interested in finding new, cheaper ways to screen for the toxin. Screening right now is very technical and very expensive, putting current methods out of reach for much of the developing world that needs it most.”

As for the chemical conversations, once the “trigger signal” is better understood, Brodhagen hopes to convert that knowledge into a treatment that could be applied to the plants; other groups are working on plant varieties that produce less of the signal to begin with. She began her research on the Aspergillus toxin in conjunction with Nancy Keller at the University of Wisconsin-Madison, and now builds on that research at WWU.

“It’s a fascinating topic – and to know how many lives could potentially be saved by it makes the research even more important,” Brodhagen said.