Fungal Pests Reassessed

BTI researcher maps the gene expression of a fungus to better understand how the microorganism eats.

By Allison Kronberg

Some fungi have developed a bad reputation as pests eating wood from the buildings where people live and work. But BTI researcher Jonathan Schilling is challenging old assumptions and finding new reasons to study the ubiquitous microorganisms.

Research in Schilling’s fungal biology lab suggests that plant- or wood-degrading fungi may find their way into a variety of new technologies, from insulation and indoor air filtration, to biofuel production.

“Since I’ve been at the University of Minnesota, I’ve branched out from looking at these organisms as pests to looking at their potential in biotechnology, as well as their importance in nature,” Schilling says.

The United States Department of Energy has funded Schilling to study specific mechanisms that control how fungi eat. “The research could help biofuel companies understand the steps a fungus takes when it degrades plants,” Schilling says.

According to Schilling, the companies have an interest in finding alternative ways to make fuel from biomass, because current processes are costly and require multiple biochemical steps. Some fungi are able to consolidate those steps, and if companies are able to tap into that ability, it could make biofuels cheaper for consumers.

A recent DOE grant, is called Connectomics — a term borrowed from neurology. The term is derived from a method of study usually used to map the real-time expression of the nerves in the human brain. Schilling has applied this method to the gene expression of fungal systems.

To produce the maps, Schilling and his lab grow a fungus named Postia placenta on wood wafers. The team then cuts the wafers into slices, like a loaf of bread, and analyzes each slice. When they put the data back together, it produces a connectome map, which shows how the fungus expresses genes and operates differently at various growth regions.

But the fungus works very slowly, so commercial use may not be likely just yet.

Instead, Schilling hopes future researchers will take advantage of the maps, using the information on fungal genome and gene expression to create new technologies or improve existing ones.

“On the science side, we’re providing a service,” Schilling says. “I offer tools. Other researchers need to go out and solve practical problems.” Schilling is hopeful that a PNAS paper, which he anticipates will be published in early fall, will be a jumping off point for others to engage with and find applications for his research.

Schilling and his students work with biomaterial companies throughout the country on research ranging from the study and application of fungi as an adhesive for window and door companies, to illuminating the characteristics of Scoby — the fungus used to produce the unconventional tea remedy, kombucha. This fall he will be teaching a new course in applied mycology. foster a new generation of scientists interested in fungi. The variety of application shows that fungal “pests” have the potential to create biotech solutions, too.

Mushrooms in the Marketplace

When they aren’t researching biotech applications of fungi, students in the Mycology Club engage with local communities by selling edible mushrooms at the University of Minnesota Farmers Market.

Standing in the pouring rain might not make a lot of people happy, but as graduate student Gerald Presley turned a small umbrella-like wine cap mushroom upside down to explain how its gill margin would expand as it matured, he had a smile on his face. More rain means more fungi — and that’s good for a fungal garden.

Presley is a graduate student in lab of BTI member Jonathan Schilling (BTI/Plant Pathology). He is also president of the UMN Mycology Club. The student group hosts workshops, lectures, and activities related to fungi. They also tend the fungal garden.

The garden has hundreds of logs blooming with fungi, so the group has also been able to raise money and interact with the local community by selling mushrooms not used    for research at the Farmers Market.

“It’s always good to find a practical application outside of the laboratory,” Presley says. “It’s been great for us.”

The club first starting selling mushrooms at the farmers market in 2013, two years after it was founded. It sells a variety of edible fungi, including shitake, wine cap, and oyster mushrooms. The Mycology Club has since teamed up with the certified organic student farm Cornercopia, which sells the mushrooms at its stand, as well.

“People like the mushrooms,” Presley said. “So they’ll come to the stand… and then they might buy some of [Cornercopia’s] stuff, too.”

Cornercopia locations — outside the Andrew Boss Meat Lab in St. Paul and in  Gateway Plaza on the East Bank — are ideal because they attract customers beyond the student body. Local chefs have even begun purchasing student-grown mushrooms for their restaurants.

The stand has shoppers talking about mushrooms. “We hear people say things like, ‘Oh, what I do with mushrooms is…’ or ‘I found a bunch of morels’ or ‘I’ve got this spot with a bunch of chanterelles this year,” Presley says. “People who come up and actually talk to us, they’ve always got their story, and it’s a chance for us to teach.”

The Mycology Club sells the mushrooms for about $10 per pound, earning about $200 over the past two seasons. The small profit, along with grant money and proceeds from selling mushroom spawn, are more than enough to support the low-cost group. “It’s kept the club alive,” Presley explains.

The club uses the money to fund biannual barbeques, teaching workshops, and guest speakers. When Presley and other student officers graduate, they will tap the 300 students on the Mycology Club’s email list so the club can continue to sell fungi grown by a new crop of mycologists.