Researchers in the US and Britain have discovered an enzyme which eats plastic and can help solve the global problem of more than eight million tons of plastic pollution being dumped into the world's oceans every year.

Scientists at the University of Portsmouth and the US Energy Department?s National Renewable Energy Laboratory researched on a naturally occurring bacterium discovered in Japan a few years ago, believed to have evolved in a waste recycling center. Known as Ideonella sakaiensis, it appears to feed exclusively on polyethylene terephthalate (PET), used widely in plastic bottles.

The researchers' goal was to understand how one of its enzymes-called PETase-worked, by figuring out its structure. But they ended up accidentally engineering an enzyme which was even better at breaking down PET plastics. Using a super-powerful X-ray, 10 billion times brighter than the Sun, they were able to make an ultra-high-resolution three-dimensional model of the enzyme.

Scientists from the University of South Florida and the University of Campinas in Brazil did computer modeling which showed PETase looked similar to another enzyme, cutinase, found in fungus and bacteria. So they mutated the PETase active site to make it more like cutinase, and unexpectedly found that this mutant enzyme was even better than the natural PETase in breaking down PET.

Researchers say they are now working on further improvements to the enzyme, with the hope of industrial use in breaking down plastics.

Source: https://www.portsmouth.co.uk/