Scientists accidentally created a mutant, plastic-eating enzyme

Some of humanity's greatest scientific inventions, penicillin, x-rays, pacemakers, microwaves, were created after researchers accidentally discovered how they might work.

Now we can add a new and monumental creation to that list: a mutant enzyme that begins to degrade the plastic in its original and natural components, discovered by pure accident.

Two years ago, Japanese scientists discovered a plastic – dominant bacterium that could break down polyethylene terephthalate (PET) plastics in about six weeks by secreting an enzyme. PET is typically found in plastic bottles and takes 400 years to degrade naturally.

To see how the enzyme that killed PET works, a different group of scientists modified its molecular structure to see how much it would reduce the rate of degradation. Against their craziest expectations, the manipulated enzyme broke PET plastics faster than the original.

John McGeehan, a professor at the University of Portsmouth, UK, led the investigation, and told Guardian that, while the discovery was "a bit surprising", he is incredibly enthusiastic about the implications .

While the modified enzyme was only "20% better" than the original, McGeehan said the percentage was irrelevant: "It tells us that the enzyme is not yet optimized, it gives us the possibility to use all the technology used in other enzyme developments for years and years and make a super-fast enzyme. "

Other industrial enzymes for purposes such as the production of biofuels have apparently been supercharged to work" 1,000 times faster "than natural bacterial enzymes" in a few years ", and the McGeehan team wants to replicate that speed for their PET destroyer.

Currently, the enzyme takes "a few days" to start decomposing the plastics, and approximately six weeks to finish the process. Divide 42 days by 1,000, and you're only watching 10 hours. Fully optimized, mass-produced enzymes that are non-toxic and biodegradable could have a significant impact on our huge plastic piles in a short period of time.

A solution that is desperately needed

Over one million plastic bottles per minute are produced and nations overflowing with plastic are pouring these bottles into the sea, where they form piles that destroy the Oceanic habitat. And to replace those bottles, plastics manufacturers drill for oil to produce more PET.

"Oil is cheap, so virgin PET is cheap," McGeehan said, but recycling plastics in plastic materials "we will not need to extract more oil."

To combat these islands of ever-growing garbage, scientists like McGeehan will try to convert their enzyme into an aerosol that can be deployed on floating debris.

Most scientists seem to find this promising, but a professor at the University of Manchester, Adisa Azapagic, warned the Guardian that the rapid dissolution of these plastics could have unintended consequences.

"A full life cycle assessment would be needed to ensure that the technology does not solve an environmental problem (waste) at the expense of others, including additional emissions of greenhouse gases," Azapagic said.

Via Engadget

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