This Maine scientist explores the wonders of microbes — and puts them to work

Anne Madden still has the heels on.

Tucked beneath a flowing dress patterned with vivid scans of yeast cells, the gold wasp pendant resting at her collar, the Yarmouth microbiologist cuts a striking figure — and one that's turned heads everywhere from TED conferences to technology summits. For Madden, the science-themed wardrobe is intentional. She wants students, especially young women, to see what a scientist can look like.

Madden, 42, has built a career finding living things too small for the human eye and putting them to work. Bacteria, viruses, fungi — microbes, collectively — get a bad rap, associated mostly with infections and crop failures. But Madden sees them differently. The vast majority of microbial species have never been studied by Western science, and the ones that have been examined offer a treasure trove of practical, and sometimes surprising, uses.

"Ninety percent of these species remain unknown to Western science, and more than just being unknown, they help us in ways that are under-appreciated," she said.

That mission of discovery and application led Madden to found The Microbe Institute, a nonprofit that operates partly from her Yarmouth home and partly through a network of research and educational partners. Its stated goal is "democratizing microbial discovery" — opening the door for anyone, not just credentialed scientists, to engage with the microbial world.

Madden grew up exploring the tidepools and waters of Casco Bay in Falmouth, where she graduated from high school in 2002. Her chemistry teacher, Andrew Njaa — who recently retired after 29 years teaching in the district — remembers a student who stood out from her peers.

"She was very serious about the science and incredibly careful and thorough, beyond where most kids would be," Njaa said. "She was one of the first students here that I had that just really blew me away."

Madden went on to Wellesley College, where biology led her into the world of microbes, and then earned a doctorate at Tufts University, studying the relationship between paper wasps and the microscopic organisms living alongside them. That research produced an unexpected breakthrough: a species of yeast, Lachancea thermotolerans, found in wasp nests across New England, that turned out to be exceptionally good at producing sour beer — typically a difficult flavor for brewers to achieve without chemical additives or bacteria borrowed from yogurt production.

The yeast creates both sour notes and floral aromas in a single organism, behaving like a conventional brewing yeast while delivering the complexity that brewers chase. "Flavor is a very hard thing for a yeast to create, and they do it beautifully," Madden said.

The discovery reshaped parts of the craft beer industry. Madden co-founded a biotechnology startup, also called Lachancea, to distribute the yeast commercially. Many brewers who rely on it today have no idea where it came from, she said.

That kind of outcome — a microbe pulled from an unexpected corner of nature and turned into a real-world solution — is exactly what Madden tries to engineer. She describes two approaches to matching organisms with problems. In one, she starts with an issue and hunts for a microbe that can solve it. She once worked with partners in Morocco searching for an alternative to synthetic dyes used in the traditional carpet-weaving industry, dyes that pose health risks to the people handling them. The hunt led to a microbe capable of producing a vibrant purple pigment naturally.

"We just have to think about where it may have evolved in the world, and then what are the steps we can take to bring it into a lab," she said.

The other approach is to start with an organism and ask what it might be good at — the same logic that turned wasp-nest yeast into a brewing staple. She compares the process to a guidance counselor's. "'What are your interests? What are you exceptional at? Where's the match?'"

The Microbe Institute connects researchers pursuing these matches with educators and artists working to make the microbial world visible and approachable. In Maine, Madden has brought hands-on programming to schools, including a project with sixth graders at Gray-New Gloucester schools in which students painted with invisible yeast cells, watching their artwork emerge as the yeast bloomed and became visible. This summer, the institute is collaborating with the Museum of Beadwork in Portland on a special exhibit of microbes and mushrooms, featuring beadwork from community members and opening with science workshops on July 11 and 12.

The microbial research community in Maine is small, according to Robert Wheeler, a professor of microbiology at the University of Maine who studies the fungus Candida. Most microbiologists working in the state focus on combating harmful microbes, he said, which makes Madden's applied-discovery approach distinctive.

"Understanding which microbes could be useful for people and developing those for some utility is a really exciting and fascinating thing that she's doing," Wheeler said. "I think that's going to enrich a lot of aspects, potentially, of education and research that happens in the state, and possibly in industry as well."

In June, Madden was honored by the National Geographic Society with a Wayfinder Award, presented by Kia. The award recognizes 15 international scientists, educators, and storytellers working to care for the natural world. Madden was the only United States recipient.

She has also been a visible public voice for microbes beyond academia. Her 2017 TED Talk about the microbial life that shares our homes and bodies has drawn more than 1.7 million views. When she speaks at conferences, she dresses for the occasion — the yeast-patterned dress, the gold wasp necklace, and a rotating collection of elaborate, microbe-themed hats she wears to draw questions and start conversations. She's worn the look since her high school days.

That visibility matters to her. Madden said she had few role models who looked like her when she was in high school, and she wants to change that for the next generation. When students visit her at the Roux Institute, where she partners on research, or when she visits classrooms, she talks about growing up in Maine and coming back. She returned to the state in 2022, drawn by family and by what she sees as Maine's growing innovation ecosystem, anchored in part by the Roux Institute.

"They're surprised that a Mainer like them can go out in the world, go to jungles, explore these different spaces," she said.

This August, Madden will be off again. She's heading to the Peruvian Amazon to collect microbes from a river so hot it boils, organisms adapted to survive conditions that would destroy most life. Whether those heat-loving microbes might one day contribute to space exploration is an open question, but it's exactly the kind of possibility she has built her career around.

For Madden, the goal goes beyond individual discoveries. She wants to shift how people think about the smallest forms of life around them.

"My goal ultimately is to change … all of society's perspectives about the microbial world, so that the first thought isn't 'gross' or, 'Oh, I've never thought about the microbes that live near me,' but rather to see wonder and sources of hope and innovation all around us," she said.

Whether she's walking into a classroom, presenting at an international conference, or suiting up for a trek into the Amazon, Madden is working toward the same idea — that microbes, given the chance, have a lot to offer.