Could we solve the plastic pollution crisis with a mutant enzyme? At a trash dump in 2016, Japanese researchers discovered the first known bacterium that had evolved to consume plastic. The Guardian reports that an international team of researchers began studying the bacterium to understand how it functioned — and then accidentally engineered it to be even better.
Research led by University of Portsmouth and National Renewable Energy Laboratory (NREL) teams engineered an enzyme able to break down plastic bottles made of polyethylene terephthalate (PET). NREL said the bad news about the find of the bacterium in the Japanese dump was that it doesn’t work quickly enough for recycling on an industrial scale. But while manipulating the enzyme, the international team inadvertently improved its ability to devour plastic.
Related: Newly discovered plastic-eating bacteria could help clean up plastic waste around the world
John McGeehan, University of Portsmouth professor, told The Guardian, “It is a modest improvement — 20 percent better — but that is not the point. It’s incredible because it tells us that the enzyme is not yet optimized. It gives us scope to use all the technology used in other enzyme development for years and years and make a super-fast enzyme.”
This mutant enzyme begins degrading plastic in a few days, a sharp contrast to the centuries it would take for plastic bottles to break down in the ocean. “What we are hoping to do is use this enzyme to turn this plastic back into its original components, so we can literally recycle it back to plastic,” McGeehan told The Guardian. “It means we won’t need to dig up any more oil and, fundamentally, it should reduce the amount of plastic in the environment.”
Chemist Oliver Jones of RMIT University, who wasn’t part of the research, told The Guardian this work is exciting, and that enzymes are biodegradable, non-toxic, and microorganisms can produce them in big quantities. He said, “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.”
The journal Proceedings of the National Academy of Sciences published the research. Scientists from the University of Campinas in Brazil and the University of South Florida contributed.
Scientists accidentally create mutant enzyme that chomps plastic for lunch [Inhabitat]