Quantcast
Environmental News for a Healthier Planet and Life

Scientists Accidentally Develop 'Mutant' Enzyme That Eats Plastic

Science

Researchers in the UK and the U.S. have inadvertently engineered an enzyme that eats up plastic.

The enzyme is able to digest PET (polyethylene terephthalate)—the same material used in the ubiquitous plastic bottle that's clogging up landfills, coastlines and oceans around the world.


Amazingly, this discovery only happened by chance. Scientists from the University of Portsmouth in the UK and the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) were examining the structure of a natural enzyme, Ideonella sakaiensis, found in 2016 at a Japanese waste recycling center. This enzyme could already break down PET plastic—it just doesn't do it very quickly.

To understand how Ideonella sakaiensis evolved, the research team "tweaked" the structure of the enzyme by adding some amino acids, according to John McGeehan, a Portsmouth professor who co-led the work. They ended up creating an enzyme that worked even faster than the natural one.

"Surprisingly, we found that the PETase mutant outperforms the wild-type PETase in degrading PET," said NREL materials scientist Nic Rorrer.

McGeehan added, "Serendipity often plays a significant role in fundamental scientific research and our discovery here is no exception."

The modified enzyme, called PETase, can break down PET in just a few days—a stunning discovery that could help fight the world's escalating plastic crisis.

Electron microscope image of enzyme degrading PET plastic Dennis Schroeder / NREL

"After just 96 hours you can see clearly via electron microscopy that the PETase is degrading PET," said NREL structural biologist Bryon Donohoe.

"And this test is using real examples of what is found in the oceans and landfills."

As BBC News explained, PETase works by reversing the manufacturing process by reducing polyesters back to their building blocks so it can be used again.

When you drink soda, water or juice from a plastic bottle, those bottles are almost never made from recycled plastic. Additionally, as the Guardian noted, the plastic bottles that do get recycled can only be turned into polyester fibers for carpet or fabric.

But this new finding suggests a way to turn plastic bottles back into plastic bottles.

"They could be used to make more plastic and that would avoid using any more oil ... Then basically we'd close the loop. We'd actually have proper recycling," McGeehan told BBC News.

The team's finding was published Monday in the journal Proceedings of the National Academy of Sciences.

The researchers are now working to improve PETase to see if it can work on an industrial scale. About one million plastic bottles are purchased around the world every minute, with that number predicted to increase another 20 percent by 2021.

"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," McGeehan said.

EcoWatch Daily Newsletter

The Ernest N. Morial Convention Center in New Orleans, Louisiana has been converted to a 1,000-bed field hospital for coronavirus patients to alleviate stress on local hospitals. Chris Graythen / Getty Images

An area in Louisiana whose predominantly black and brown residents are hard-hit by health problems from industry overdevelopment is experiencing one of the highest death rates from coronavirus of any county in the United States.

Read More Show Less
A woman lies in bed with the flu. marka/Universal Images Group via Getty Images

A central player in the fight against the novel coronavirus is our immune system. It protects us against the invader and can even be helpful for its therapy. But sometimes it can turn against us.

Read More Show Less
Sponsored
Several flower species, including the orchid, can recover quickly from severe injury, scientists have found. cunfek / iStock / Getty Images Plus

Calling someone a delicate flower may not sting like it used to, according to new research. Scientists have found that many delicate flowers are actually remarkably hearty and able to bounce back from severe injury.

Read More Show Less
A Boeing 727 flies over approach lights with a trail of black-smoke from the engines on April 9, 2018. aviation-images.com / Universal Images Group via Getty Images

With global air travel at a near standstill, the airline industry is looking to rewrite the rules it agreed to tackle global emissions. The Guardian reports that the airline is billing it as a matter of survival, while environmental activists are accusing the industry of trying to dodge their obligations.

Read More Show Less
A National Guard member works on election day at a polling location on April 7, 2020 in Madison, Wisconsin. Andy Manis / Getty Images.

ByJulia Baumel

The outbreak of COVID-19 across the U.S. has touched every facet of our society, and our democracy has been no exception.

Read More Show Less