With public awareness of the world’s plastic pollution problems on the rise, a timely and accidental breakthrough may now be poised to offer a solution.
In 2016, Japanese researchers discovered bacteria able to break down polyethylene terephthalate (PET), a type of plastic that is among the most widely used in the world. The bacteria, called Ideonella sakaiensis, is able to consume the plastic as a source of carbon and energy. That discovery alone was considered a breakthrough towards allowing the plastic to biodegrade. But now, scientists in the UK and US have inadvertently created an enzyme that is even more capable of efficiently breaking down the plastic. The findings were published Monday in the journal Proceedings of the National Academy of Sciences, and the story was covered by the Huffington Post on Monday.
Researchers at University of Portsmouth and the National Renewable Energy Laboratory in the US, while studying the bacteria’s structure, exposed bacteria to X-ray beams 10 billion times brighter than the sun, allowing them to study their individual atoms. While working with the bacteria’s structure to learn more about them, the team accidentally created a mutant enzyme with new capabilities.
According to one of the team’s lead scientists, John McGeehan:
“Serendipity often plays a significant role in fundamental scientific research and our discovery here is no exception. 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.”
The team is now working to develop the enzyme for use on an industrial scale, which will be necessary to help tackle the growing crisis of plastic pollution. One million plastic bottles are purchased every minute worldwide, and most of them are made from PET, which can take as long as 400 years to biodegrade. Many of these plastics have ended up in the ocean, leading the UN Oceans chief to call the issue a “planetary crisis.”
While PET can be recycled, over half of the plastics worldwide are never recycled.
The newly discovered enzymes would be able to process PET waste into clear plastic for new bottles. This could be key to speeding solutions to the problem. For example, Coca-cola has committed to increase the recycled content of its plastic bottles 50 percent by 2020, but companies like Coca-cola have aesthetic concerns over the appearance of bottles made entirely from recycled plastic, which has slowed progress thus far.