New super-enzyme eats plastic bottles six times faster

[nitpicker]

https://www.theguardian.com/environment/2020/sep/28/new-super-enzyme-eats-plastic-bottles-six-times-faster

New super-enzyme eats plastic bottles six times faster

Damian Carrington Environment editor

Mon 28 Sep 2020 20.38 BST Last modified on Mon 28 Sep 2020 20.39 BST

A super-enzyme that degrades plastic bottles six times faster than before has been created by scientists and could be used for recycling within a year or two. The super-enzyme, derived from bacteria that naturally evolved the ability to eat plastic, enables the full recycling of the bottles. Scientists believe combining it with enzymes that break down cotton could also allow mixed-fabric clothing to be recycled. Today, millions of tonnes of such clothing is either dumped in landfill or incinerated.
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The super-enzyme was engineered by linking two separate enzymes, both of which were found in the plastic-eating bug discovered at a Japanese waste site in 2016. The researchers revealed an engineered version of the first enzyme in 2018, which started breaking down the plastic in a few days. But the super-enzyme gets to work six times faster.

“When we linked the enzymes, rather unexpectedly, we got a dramatic increase in activity,“ said Prof John McGeehan, at the University of Portsmouth, UK. “This is a trajectory towards trying to make faster enzymes that are more industrially relevant. But it’s also one of those stories about learning from nature, and then bringing it into the lab.”

French company Carbios revealed a different enzyme in April, originally discovered in a compost heap of leaves, that degrades 90% of plastic bottles within 10 hours, but requires heating above 70C.

The new super-enzyme works at room temperature, and McGeehan said combining different approaches could speed progress towards commercial use: “If we can make better, faster enzymes by linking them together and provide them to companies like Carbios, and work in partnership, we could start doing this within the next year or two.”

The 2018 work had determined that the structure of one enzyme, called PETase, can attack the hard, crystalline surface of plastic bottles. They found, by accident, that one mutant version worked 20% faster. The new study analysed a second enzyme also found in the Japanese bacteria that doubles the speed of the breakdown of the chemical groups liberated by the first enzyme.

Bacteria that break down natural polymers like cellulose have evolved this twin approach over millions of years. The scientists thought by connecting the two enzymes together, it might increase the speed of degradation, and enable them to work more closely together.

The linked super-enzyme would be impossible for a bacterium to create, as the molecule would be too large. So the scientists connected the two enzymes in the laboratory and saw a further tripling of the speed. The new research by scientists at the University of Portsmouth and four US institutions is published in the journal Proceedings of the National Academy of Sciences.
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[Wicked Blue]

1. If this enzyme gets loose

it's going to start chomping through all our plastic like Pac-Man.

One day someone will be walking in their Crocs, look down and see bare feet.

Try to pay with a credit card, and whoops, the card has been devoured.

Kids will cry when their Legos and Barbies vanish into thin air.


Actually, I hope this will solve our worldwide problem with having too much plastic messing up the planet.

Thanks for posting this.

[dhol82]

2. Why am I seeing a sci-fi movie about a dystopian future where all plastic has been eaten?

[msongs]

3. what happens to waste created from this process? doesnt go away, just changes form nt

[murpheeslaw]

4. There was a Sci-fie story about this

The story ended with the protagonist dying in an airplane crash because the wiring insulation was eaten away and the systems all shorted out.