Could we solve the plastic pollution crisis with a mutant enzyme? Hidden in the soil at a plastics recycling plant, researchers unearthed a microbe that had evolved to eat the soda bottles dominating its habitat, after you and I throw them away.
The modified enzyme, known as PETase, can start breaking down the same material in just a few days. The research team believes there is potential to accelerate this process even more with further modification.
Researchers have created a chemical that can break plastic down in a matter of hours - compared to the hundreds of years it takes for it to decompose in the Nature. "Some of those images are horrific", said McGeehan. These differences indicated that PETase may have evolved in a PET-containing environment to enable the enzyme to degrade PET.
This could revolutionise the recycling process, allowing plastics to be re-used more effectively.
More: What would happen if everyone recycled? Its findings were published on Monday in the Proceedings of the National Academy of Sciences journal.
A high definition 3D model of the enzyme was created, using the powerful x-ray beamline at Diamond Light Source in Oxfordshire.
Hypothesising that the PETase enzyme must have evolved in the presence of PET to figure out how to degrade the plastic, the researchers mutated PETase's active site, to see if they could bring it closer to another enzyme, called cutinase. "We were thrilled to learn that PETase works even better on PEF than on PET", said Beckham.
This suggests that the natural enzyme isn't fully optimized yet and there is the potential to engineer it. Plastic pollution is fast becoming one of the biggest environmental issues of our time.
The research was led by teams at the University of Portsmouth in the United Kingdom and the USA department of energy's National Renewable Energy Laboratory (NREL).
According to Innova Market Insights data, 58 percent of globally launched food and beverage products are packaged in plastic, a 5 percent increase from 2013, while 96 percent of all newly launched water products in 2017 are packaged in PET bottles.
Earlier work had shown that some fungi can break down PET plastic, which makes up about 20% of global plastic production.
"Other types of plastic could be broken down by bacteria currently evolving in the environment, McGeehan said: "People are now searching vigorously for those".
Oliver Jones, a Melbourne University chemistry expert said, "Enzymes are non-toxic, biodegradable and can be produced in large amounts by microorganisms".
By contrast, the new synthetic enzyme could allow for plastic to be quickly - and endlessly - recycled.