Jan 26 2017
Could Yeast and Fungi Be Used to Rid Our Water of Organic Pollutants?
As our society evolves and changes so do the pollutants that find their way into our waste streams. One area of growing concern is organic compounds from pharmaceuticals and personal care products. Traditional treatment methods are often ineffective at removing these compounds, some of which have deleterious effects on human health, such as endocrine disrupting properties.
Professor Na Wei in Notre Dame’s Department of Civil & Environmental Engineering & Earth Sciences, who speaks animatedly about her work, is attempting to solve this problem by harnessing the power of enzymes and microorganisms. For Professor Wei this research has personal significance that goes back to the reason she became an environmental engineer in the first place.
Wei grew up in China’s Sichuan Province. Her mother worked at a wastewater treatment plant. After secondary treatment, the effluent from the plant was released into a large tank that teemed with fish. As a young girl, Wei remembers spending many afternoons fishing from this tank, waiting for her mom. The fish seemed to be hungry or else Wei was skilled with a hook and line for she often brought home a bounty. She generously shared her harvest with her neighbor, who ran a small restaurant. Everyone believed that these fish were safe to eat.
It wasn’t until years later that Wei learned that these fish might have contained harmful pollutants. This realization affected Wei deeply and inspired her to pursue environmental engineering.
Now Wei is using her training in molecular and synthetic biology to address this environmental engineering challenge from an interdisciplinary approach.
In nature, the white-rot fungi produces super-enzymes that breakdown complex organic compounds. The enzymes themselves, however, are not stable in water and therefore on their own are not suitable for wastewater treatment. Researchers are hard at work trying to come up with a way to utilize these enzymes. Some labs are trying to develop matrices to stabilize these enzymes. Professor Wei’s lab is taking a slightly different approach. They’ve engineered baker’s yeast, which reproduces easily, to express the enzymes of interest as a surface display. Thus the yeast acts as a biocatalyst to degrade the organic pollutants.
Professor Wei’s lab has already developed and tested the efficacy of using this system to degrade Bisphenol A (BPA), which is found in many plastics, and Sulfamethoxazole, an antibiotic. The results were promising. Her lab is now working to optimize this system and exploring what other pollutants could be treated using this technology.
Wei dreams that someday this technology will be implemented at wastewater treatment plants to ensure that effluent is completely safe for humans and the environment.
In addition to developing biocatalysts for water reclamation, Wei’s lab is doing research on a number of other pressing environmental concerns. Her lab is working on turning waste products into energy sources, controlling vectors of infectious disease, and most recently harvesting phosphorous from waste streams so that it can be reused.