Scientists have created an ‘enzyme cocktail’ which can break down plastic up to six times faster than previously possible. This new ‘cocktail’ was created by combining a re-engineered version of ‘PETase’ (an enzyme which has evolved to break down plastic) with a second enzyme known as ‘METase’. By combining these two enzymes they were able to break down a common thermoplastic which usually takes centuries to biodegrade, in just days. This could enable PET plastics to be recycled infinitely and could potentially limit the amount of plastic that is manufactured and discarded.
Professor McGeehan said: “Gregg and I were chatting about how PETase attacks the surface of the plastics and MHETase chops things up further, so it seemed natural to see if we could use them together, mimicking what happens in nature.
“Our first experiments showed that they did indeed work better together, so we decided to try to physically link them, like two Pac-men joined by a piece of string.
“It took a great deal of work on both sides of the Atlantic, but it was worth the effort – we were delighted to see that our new chimeric enzyme is up to three times faster than the naturally evolved separate enzymes, opening new avenues for further improvements.”
Currently over 50% of plastics are single use, with over 300 million tonnes being produced each year, 90% of which isn’t even recycled. With an ever-growing demand on the horizon, this could be a viable solution in terms of recycling plastics.