Engineering bacterial sex to remove plastic waste in water systems
Researchers at the University of Waterloo are taking a novel approach to tackle the critical issue of microplastic pollution in water systems. The research team is engineering bacteria that already exist in wastewater to break down Polyethylene terephthalate(PET).
Plastic waste in water systems is an urgent environmental concern. PET plastics degrade into microplastics that adversely impact the ecosystems of our lakes, rivers, and oceans.
Professor Marc Aucoin from the Department of Chemical Engineering and Professor Brian Ingalls from the Department of Applied Mathematics with PhD student Aaron Yip are developing a technique that enables wastewater bacteria to break the links between plastic molecules so PETs can be degraded.
In a natural process referred to as “bacterial sex”, cells can exchange genetic material with their neighbours. Researchers can take advantage of that natural process to deliver genetic information from an engineered ‘donor’ strain to a target population of interest. In this case, that genetic transfer results in the ability to break down plastics.
“These results provide a foundation for further development of strategies to achieve plastic degradation within existing water treatment systems, says Ingalls. “In complementary work, we’re developing computational tools that will support model-based design of such interventions.”
The vision of the research group is to have an operating unit in a wastewater treatment plant with a biological filter. Bacteria injected with the new microbiome would directly break down microplastics in wastewater treatment plants.
“We have a platform where we can engineer a wide variety of bacteria from an environmental sample to break down PET plastics,” says Yip.
The next steps in this research will be characterizing the gene delivery process and assessing the efficiency of the degradation process in a range of environmental conditions.
“We’ve shown proof of concept that this technique works, and the bacteria take up the genetic vector and perform quite well in breaking down plastics,” says Aucoin, director of the Applied Virus and Complex Biologics Bioprocessing Research Lab. “Although the likely approach will be wastewater facilities, we dream of a way of cleaning up the plastic waste accumulating in the oceans.”
The study was recently published in the journal Microbial Biotechnology.