As concern for plastic pollution mounts, scientists have discovered a naturally occurring enzyme capable of digesting certain plastics in a matter of days versus the hundreds of years it would take to break down otherwise.

Researchers from Britain’s University of Portsmouth and the U.S. Department of Energy’s National Renewable Energy Laboratory discovered that the enzyme, Ideonella sakaiensis 201-F6, is able to digest polyethylene terephthalate (PET) a plastic used to manufacture water bottles.

"[PET] has only been around in vast quantities over the last 50 years, so it's actually not a very long timescale for a bacteria to have evolved to eat something so man-made," commented Professor John McGeehan, director of the Institute of Biological and Biomedical Sciences in the School of Biological Sciences at Portsmouth.

Found in 2016 at a bottle recycling site in the Japanese city of Sakai, the team of researchers originally set out to study the structure of Ideonella sakaiensis but instead mistakenly engineered an enzyme that could break down PET plastics.

Calling the enzyme PETase, the team of researchers also tested it on PEF plastic (a possible plant-based alternative PET that is also slow to degrade).

"We were absolutely stunned when we did that experiment because it actually works better on PEF than PET," said Prof McGeehan.

"Although the improvement is modest, this unanticipated discovery suggests that there is room to further improve these enzymes, moving us closer to a recycling solution for the ever-growing mountain of discarded plastics," said McGeehan.