A group of scientists have created a “super-enzyme” that could, they hope, help to solve the world’s plastic problems. The super-enzyme that eats plastic could be “a significant leap forward” in finding solutions to tackle the pollution crisis, scientists hope.
Professor John McGeehan, director of the Centre for Enzyme Innovation (CEI) at the University of Portsmouth, said that unlike natural degradation, which can take hundreds of years, the super-enzyme is able to convert the plastic back to its original materials, or building blocks, in just a few days. “Currently, we get those building blocks from fossil resources such as oil and gas, which is really unsustainable,” Professor McGeehan told.
This new super-enzyme is able to break down the plastic at room temperature, setting it apart from the enzyme that the French company Carbios discovered in April. The Carbios enzyme started to work when the plastic was heated to 65 to 72 degrees Celsius, or 149 to 161 degrees Fahrenheit, which is the range when plastic bottles start to soften and melt.
In 2018, Prof McGeehan and his team accidentally discovered that an engineered version of one of the enzymes, known as PETase, was able to break down plastic in a matter of days. As part of their current study, published in the journal Proceedings of the National Academy of Sciences, the team mixed PETase with the second enzyme, called MHETase, and found “the digestion of the plastic bottles literally doubled”. The researchers then connected the two enzymes together in the lab, like “two Pac-men joined by a piece of string”, using genetic engineering. Prof McGeehan, who is one of the study authors: “This allowed us to create a super-enzyme six times faster than the original PETase enzyme alone.
According to a study, the amount of plastic waste flowing into the ocean and killing marine life could triple in the next 20 years, unless companies and governments can drastically reduce plastic production. China is the top source of plastic bottles, bags and other rubbish clogging up global sea lanes, according to the latest country-wise data available. Around the world, one million plastic drinking bottles are purchased every minute, while up to 5 trillion single-use plastic bags are used worldwide every year. In total, half of all plastic produced is designed to be used only once — and then thrown away.
