Last year, we shared the sad impact that plastic pollution has had on some of our planet’s most beautiful places. With recycling not turning out to be the savior it was made out to be, solutions to our growing plastic problem can seem distant and complex.
We have seen some glimmers of hope from both human innovation and nature itself, however. In 2016, a bacteria that evolved with the ability to break down plastic was discovered in a Japanese waste site. Two years later, scientists managed to engineer the mutant plastic-eating enzyme they called PETase—named for polyethylene terephthalate, the most common plastic found in bottles and food packaging—in a lab.
Here’s an explainer of how those enzymes work:
Ending Plastic Pollution with Designer Bacteria
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Now researchers have revealed another game-changer in the plastic-eater—a super-enzyme that can break down plastic six times faster than PETase alone.
The super-enzyme is a bit of a frankenzyme, created by linking different enzymes together. “When we linked the enzymes, rather unexpectedly, we got a dramatic increase in activity,” Prof John McGeehan, at the University of Portsmouth, UK, told The Guardian. “This is a trajectory towards trying to make faster enzymes that are more industrially relevant. But it’s also one of those stories about learning from nature, and then bringing it into the lab.”
This new research has been published in the journal Proceedings of the National Academy of Sciences.
Combining enzymes could be the key to making various kinds of plastics and combined materials fully recyclable. “There’s huge potential,” said McGeehan. “We’ve got several hundred in the lab that we’re currently sticking together.”
For example, combining the plastic-eating enzymes with existing enzymes that break down natural fibers could allow fabrics made of mixed materials to be recycled, McGeehan told The Guardian. “Mixed fabrics [of polyester and cotton] are really tricky to recycle. We’ve been speaking to some of the big fashion companies that produce these textiles, because they’re really struggling at the moment.”
This newest research isn’t the first to improve upon the plastic-eating bacteria discovery. In April, a French chemistry company called Carbios shared their own mutant enzyme that can degrade 90% of plastic bottles within 10 hours. However, that enzyme, which originally discovered in a pile of composting leaves, requires heating above 70 degrees Celsius (nearly 160 degrees Fahrenheit), whereas this new super-enzyme works at room temperature.
Not that it’s a cutthroat competition. We are talking about helping out the entire planet and saving life as we know it, after all. McGeehan suggested that the researchers work together with the private sector to get the enzymes working out in the real world. “If we can make better, faster enzymes by linking them together and provide them to companies like Carbios, and work in partnership, we could start doing this within the next year or two,” McGeehan told The Guardian.
McGeehan did emphasize to CNN that the super-enzyme is “still way too slow” to be commercially viable at this point, but it is a huge step in the process. “We were actually quite surprised it worked so well,” he told CNN.
Here’s to science coming up with solutions to the problems human scientific advances have created, and here’s to learning to live in better balance with nature in the process.