Researchers in the United Kingdom and the United States are working on mutating an enzyme that eats polyethylene terephthalate (PET), used for plastic bottles.
The goal is to create a system that uses the enzymes to recycle the plastic 100 percent, according to the Guardian. Professor John McGeehan, at the University of Portsmouth, England, is leading the research. He told the Guardian that PET “is one of these wonder materials that has been made a little bit too well,” as recycling rates are generally low, and the ubiquitous plastic pollution ends up in the farthest reaches of the ocean, slowly degrading and releasing toxins over time.
McGeehan noted that bottles that are recycled are turned into opaque fibres for clothing or carpets. The mutated enzyme holds the promise of recycling clear plastic bottles back into clear plastic bottles.
That means the need to produce new plastic from oil resources might be greatly minimized. “You are always up against the fact that oil is cheap, so virgin PET is cheap,” said McGeehan.
Going Atomic on Plastic Bottles
The research, published in the journal Proceedings of the National Academy of Sciences, offers the precise structure of an enzyme produced by a bug discovered eating PET in a Japanese dump in 2016.
The researchers used X-ray technology 10 billion times brighter than the sun to reveal the enzyme’s atoms. As the team was exploring the enzyme’s structure, they reportedly improved its ability to eat PET by 20 percent. The team is now working on various methods to improve the enzyme to make it work 1,000 times faster than it’s natural state, and develop it to address plastic pollution on a systematic level.
“Enzymes are non-toxic, biodegradable and can be produced in large amounts by microorganisms,” according to Oliver Jones, a chemist at RMIT University in Melbourne, Australia, not working on the project but interviewed for the story. “There is still a way to go before you could recycle large amounts of plastic with enzymes, and reducing the amount of plastic produced in the first place might, perhaps, be preferable. [But] this is certainly a step in a positive direction.”
Scientists have theorized that waste streams could be treated with sprayed enzymes capable of breaking down the plastics.
According to the story, a patent has been filed by the researchers and those from the U.S. National Renewable Energy Laboratory in Colorado.
Learn more about how cities are addressing recycling: