Engineers have developed an enzyme, which makes it possible to degrade plastic with bacteria. This type of enzyme is already known, but it has the ability to act very quickly.
Plastic pollution is only increasing, again and again. It could even triple by 2040. It is not only necessary to find solutions to reduce it, but also to develop increasingly effective recycling mechanisms, because this pollution damages ecosystems, the health of animals and that of humans.
What if an enzyme developed in the lab could help improve the process of plastic degradation and recycling? “ The possibilities for leveraging this state-of-the-art recycling process are endless, across all industries. », Estimates the engineer Hal Alper, on the site of the university of Texas.
With his team, they created a new enzyme capable of degrading plastic in just a few hours. The discovery was published in the journal NatureApril 27, 2022.
We decompose the plastic to do something else with it: there is less accumulation
The enzyme has been named “FAST-PETase”, an acronym for “functional, active, stable, and tolerant PETase”. PETases are an already known class of enzymes that naturally allow bacteria to catalyze the hydrolysis of polyethylene terephthalate plastic. During such a process, the plastic is broken down into its basic molecular units — this is called depolymerization.
Clearly, this allows the plastic to degrade. But to make it more efficient, these engineers modified it in the laboratory using an automatic learning algorithm (close to a form of artificial intelligence). This algorithm identified 5 mutations accelerating the degradation process.
And in the lab, it works: in tests, products made from the polymer polyethylene terephthalate were broken down in a week but also, on several occasions, only 24 hours. By way of comparison, under natural conditions, this type of plastic product — bottles, clothing fabrics, etc. — normally takes several decades, or even centuries, to degrade to this point. ” When considering environmentally friendly cleaning methods, an enzyme is needed that can function in the room temperature environment. This is where our technology has a huge advantage for the future. “says Hal Alper.
But what to do after degradation of plastic components? This is an aspect also considered by the authors: in their study, they show that after depolymerization, the components can be reused by repolymerization. This means that thanks to a chemical mechanism, we can reconstitute plastic in new forms: we can create new products.
” Beyond an obvious industrialization for waste management, it would also give companies in all sectors the opportunity to take the initiative to recycle their products. writes engineer Hal Alper. A rapid plastic degradation enzyme could counteract the buildup of plastic pollution, helping the transition to more sustainable lifestyles.
