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Scientists Accidentally Create Mutant Enzyme That Eats Plastic Bottles (theguardian.com)
Scientists have created a mutant enzyme that breaks down plastic drinks bottles -- by accident. The breakthrough could help solve the global plastic pollution crisis by enabling for the first time the full recycling of bottles. From a report: The new research was spurred by the discovery in 2016 of the first bacterium that had naturally evolved to eat plastic, at a waste dump in Japan. Scientists have now revealed the detailed structure of the crucial enzyme produced by the bug. The international team then tweaked the enzyme to see how it had evolved, but tests showed they had inadvertently made the molecule even better at breaking down the PET (polyethylene terephthalate) plastic used for soft drink bottles. "What actually turned out was we improved the enzyme, which was a bit of a shock," said Prof John McGeehan, at the University of Portsmouth, UK, who led the research. "It's great and a real finding." The mutant enzyme takes a few days to start breaking down the plastic -- far faster than the centuries it takes in the oceans. But the researchers are optimistic this can be speeded up even further and become a viable large-scale process.
https://www.goodreads.com/book/show/2368220.Mutant_59
I remember news about plastic-eating bacteria back in the 90s. The local newspaper had a cartoon with bugs munching on credit cards.
Escher was the first MC and Giger invented the HR department.
Quick bit of research suggests it breaks down into terephthalic acid and ethylene glycol. http://science.sciencemag.org/.... The former is a precursor to the production of fresh PET https://en.wikipedia.org/wiki/...
If you consider that PET is comprised solely of hydrogen, carbon and oxygen, then yes, it probably does.
Like anything that breaks down hydrocarbons. Including you when you breathe.
If the enzyme gets loose? You do know what an enzyme is, don't you?
The bacteria which produced the precursor is already loose--it was a naturally occurring beast. Just how dangerous it is remains to be seen. It's worth worrying about.
But this new enzyme? It's true that enzymes aren't destroyed by their processes--that's one of their defining features--but they also don't move by themselves, so they're not going to "eat" anything they're not actively placed on. Nor do they reproduce. I think we're pretty safe.
I mean, sulfuric acid will also eat many plastics. Do you worry about sulfuric acid "getting loose" and eating your fleece jacket?
I think some people are being confused by the use of the term "mutant" in the headline. This is not a creature. It doesn't reproduce. It's a chemical. You can worry about spills, but it's never going to be a plague.
The bacteria it was derived from might become a plague, but that's an already-existing worry, since it's a naturally occurring critter which is already out there in the wild. But this is just stuff. If it "gets loose", it'll just sit there. At worst, it might contaminate the groundwater or something, but that's true of a lot of other chemicals.
From the wiki article on "deicing fluid":
Airports that use this stuff are required to have capture processes to keep this from the ground water. It doesn't sound so environmentally benign to me. The only reasons these two precursors are less dangerous is because they aren't lumps of (previously thought) poorly-bio-degradable plastic.
I was also going to point to Mutant 59: The Plastic Eaters, but someone beat me to it.
While ethylene glycol is considered toxic and propylene glycol is a food additive, both break down quickly in soils, unless the burden is so great that oxygen deprivation becomes a factor, as noted in the quote above.
Most airports (at least those I've done work for) don't do anything special to contain the runoff from deicing, other than to not discharge it to storm sewers leading to rivers and lakes.
Also, airports don't use ethylene glycol, they use propylene glycol for deicing. (For anti-icing, they use propylene glycol-based fluids modified to have high viscosity at low shear rates and low viscosity at high shear rates: that way it stays on the wings until the plane gets near takeoff speed.)
It's an *ENZYME*, not bacteria. It isn't alive. It doesn't reproduce. It isn't a virus. It does not infect organisms to cause them to make more of itself. It just helps a particular chemical change to occur.