A protein ‘similar’ to ‘Pac-Man’, which has a special appetite for plastic, could open the door to solving one of the biggest environmental problems in the world: the billions of tons of waste in landfills. Researchers at the University of Texas at Austin, USA, developed this special enzyme to destroy PET (polyethylene terephthalate), a substance that is commonly used by manufacturers in food and beverage packaging, textiles and fibers.
Its development, the study of which was published in the journal ‘Nature’, offered hope of helping to solve global pollution, allowing a complete recycling of plastic waste, which could allow large industries to recover and reuse products at the molecular level. “The possibilities are endless across all industries to leverage this cutting-edge recycling process,” explained Hal Arper, who was responsible for the study.
Watch the enzyme in action: https://t.co/cgIhFvbDR0 @LabAlper @TexasChE @UTAustin
— Texas Engineering (@CockrellSchool) April 28, 2022
“In addition to the obvious waste management industry, it also offers companies in all sectors the opportunity to lead the way in recycling their products. Through these more sustainable enzymatic approaches, we can begin to envision a true circular economy of plastics”, explained the researcher.
PET represents about 12% of all global waste – like all plastics, it is made up of long ‘string-like’ molecules. The enzyme manages to reduce it into smaller parts before chemical ‘recycling’. In some cases, plastics only take between 24 and 48 hours to fully decompose. In the oceans, for example, these products can survive for centuries.
The enzyme development process had the collaboration of Artificial Intelligence (AI), which generated new mutations to a natural enzyme called PETase, which allows bacteria to degrade PET – the computational neural network identified the most effective mutations at less than 122 degrees Fahrenheit (50 degrees Celsius), thus making it portable and affordable. Dozens of discarded plastic items were analyzed, including containers, water bottles, polyester fibers and fabrics – all made with PET. “This work really demonstrated the power of bringing different disciplines together, from synthetic biology to chemical engineering to artificial intelligence,” says study co-author Andrew Ellington.
In 2020, the world produced 367 million tons of plastic, of which less than 10% ended up being recycled. After sending this material to landfills, burning is the second most common method of plastic disposal. However, the environmental consequences are extreme, with the release of harmful gases into the air. Alternative industrial processes exist but are quite energy intensive, while biological solutions require much less effort.
The study’s authors revealed that they are increasing production of the enzyme to prepare for industrial and environmental applications – the Texas team has filed a patent and is eyeing several different uses, including cleaning up landfills and making high-end industries. production of more ecological waste. “When considering environmental cleaning applications, you will need an enzyme that can function in the environment at normal temperature. This requirement is where our technology has a huge advantage going forward,” concluded Hal Arper.
–
