Thoughts on saving the planet
Super-enzyme breaks down plastic bottles in ‘a matter of days’
From BBC Science Focus Magazine: Professor John McGeehan at work The enhanced protein is made up of two enzymes produced by a type of bacteria that feeds on plastic bottles. A so-called “super-enzyme” that eats plastic could be “a significant leap forward” in finding solutions to tackle the pollution crisis, scientists hope. The enhanced protein is made up of two enzymes produced by a type of bacteria that feeds on plastic bottles, known as Ideonella sakaiensis. 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,” he said. “But if we can add enzymes to the waste plastic, we can start to break it down in a matter of days.” He said the process would also allow plastics to be “made and reused endlessly, reducing our reliance on fossil resources”. 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. The super enzyme, which is two proteins joined together © Aaron McGeehan/Knott et al “This allowed us to create a super-enzyme [...]