While that nice the goal is to significantly reduce the use of plastics and petrochemical in general. What we are talking about is a reengining of modern tools and products. These efforts will be aggressive.
Scientists create artificial protein that can degrade PET plastics in bottles
31–40 of 110 posts
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#32As cool as this is, the word “microplastics” is a little misleading. There are dozens of types of plastic in common use, each made from a different monomer with a different chemical linkage, of which PET is only one. The engineered protein in TFA will only work on PET and we’ll need to design new proteins for the other types of plastic. (I can help with that.)
The problem with enzymes eating plastic is that enzymes are small Pacman-shaped protein blobs that are maybe 10 nanometers in diameter, whereas things made of plastic like bottles or even microplastics are huge in comparison. How do you get the little Pacman jaws around the bottle to start breaking it down?
The research paper [1] describes the authors’ effective innovation. They make a protein where one end is a pore-forming shape, and the other end is a PET cutting (called a PETase in the jargon of the field). This way, their protein can access nooks and crannies in the macroplastic shapes, allowing tons of copies of this small enzyme to fully degrade a bottle.
Without this, a great deal of physical agitation is required to break down the plastics into small enough chunks that earlier Pacman enzymes could work on, increasing the time and the cost.
I hope we’ll see the idea of linking the enzymatic “scissors” to a protein pore be used to engineer enzymes to degrade other types of plastics in the future, as the general idea of getting the catalytic machinery into physical contact with every bit of the bottle is broadly applicable to all plastics, not just PET (which is great news)
1. https://phys.org/news/2023-10-scientists-artificial-protein-...
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#33Earlier quoted context omitted.
it's fascinating to see in real time. you would think it would be Semmelweiss-esque - a lone discredited voice - but it's not. everyone seems to be fully aware of the problem and its likely dangers ... and yet the problem is as bad as ever
The reason is simple: despite their many problems, plastics are a modern day miracle material. The alternatives I see proposed may match or beat it on one or two factors, but not everything. A viable general replacement for plastic needs to beat plastic on price, weight, durability, sanitation, strength, and so much more.
or we could be willing to trade off some of these factors in order not to befoul our home
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#34Microplastics are the "lead/asbestos poisoning" of our generation, and the problem is actually far more dire than either of the former. Someday, we will look back on how we could have ever allowed microplastics into our lives with shock and awe.
I've yet to see any evidence that microplastics are toxic. Plastics are generally inert, and by the time they have broken down into microscopic pieces, most plasticizers have already been leached from the particles.
Microplastics are an ugly witness to pollution, but are likely not themselves very harmful.
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#35Earlier quoted context omitted.
The reason is simple: despite their many problems, plastics are a modern day miracle material. The alternatives I see proposed may match or beat it on one or two factors, but not everything. A viable general replacement for plastic needs to beat plastic on price, weight, durability, sanitation, strength, and so much more.
or we could be willing to trade off some of these factors in order not to befoul our home
^^^ So very much this! ^^^ It's a shame I cannot upvote this more than once.
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#36Microplastics are the "lead/asbestos poisoning" of our generation, and the problem is actually far more dire than either of the former. Someday, we will look back on how we could have ever allowed microplastics into our lives with shock and awe.
I think this is really underselling the danger of lead and asbestos. They were known to be dangerous basically since their commercial introduction and there are undeniable large scale negative health trends which are clearly attributable to both, unlike with microplastics
The negative effects of lead and asbestos are known and abatement is ongoing. There are grants being administered today to aid in their continued abatement.
The negative known effects of microplastics are emerging. The public are not as aware of the extent to which they are exposed to microplastics daily. We don't actually know the full extent of the damage being done yet, but what we do know so far is that microplastics affect neurological development, fertility, and are known endocrine-disrupters. It will take time to see the full effects of microplastics in our environment, and it's going to get worse before it gets better.
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#37This announcement sounds like something mentioned in the background on TV while the soon to be hero eats breakfast before heading to work in an underpaid thankless position. 15 minutes later the audience learns that the protein has escaped the lab, become sentient, and is assembling plastic into Godzilla.
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#38Major omitted-from-headline limitation: It only works on PET plastic. (AKA "PETE", or https://en.wikipedia.org/wiki/Polyethylene_terephthalate - recycling number "1" or "01") Quibble: "microplastics in bottles" looks far more like keyword stuffing then a sensible description.
I find the current title much more clear than requiring that people know what PET is.
And if you're familiar enough to know what plastic types exist, you probably also realize that this won't be a miracle protein that can tackle a ton of different chemicals with this one innovation/advancement.
Unless you're a chemical engineer, I can't think of a place where anyone would need to know what PET is. Bottle returns don't have different holes based on the recycling type, I can even throw glass and cans in with plastic bottles and it'll scan the label and sort it out. For me, I might have made a tentative guess that PET is used in bottles, and my dad inspects factories that produce that stuff and so it's not like I had no exposure to it (just no interest in the myriad of plastics we're trying to avoid)
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#39With these articles I always wonder what they're turned into, since headlines and introductory paragraphs always conveniently omit that. These seem to be the relevant parts of the article:
> degrading PET [particles] and reducing them to their essential components, which would allow them to be broken down or recycled
> "One variant breaks down the PET particles more thoroughly, so it could be used for degradation in sewage treatment plants. The other gives rise to the initial components needed for recycling. In this way we can purify or recycle, depending on the needs," explains Laura Fernández López
Hmm, so that sounds like it's a step forwards (working the problem), but not yet a solution that can recycle PET into something anyone can use
Edit: this is why I'm asking...
Article: "... the bacterium Idionella sakaiensis, which is capable of degrading this type of plastic and was discovered in 2016 in a packaging recycling plant in Japan."
Wikipedia on Ideonella sakaiensis: "[they] mineralize 75% of the degraded PET into carbon dioxide" (to be fair, it also produces a "MHETase enzyme" which "could also be optimized and used in recycling or bioremediation applications") https://en.wikipedia.org/wiki/Ideonella_sakaiensis
Re: Scientists create artificial protein that can degrade PET plastics in bottles
#40Earlier quoted context omitted.
The reason is simple: despite their many problems, plastics are a modern day miracle material. The alternatives I see proposed may match or beat it on one or two factors, but not everything. A viable general replacement for plastic needs to beat plastic on price, weight, durability, sanitation, strength, and so much more.
or we could be willing to trade off some of these factors in order not to befoul our home
It is sort of weird because people around the world are staving, while we have tons of food waste in the west. So there is in some sense a crisis and plastics are a tool that could be used to help solve it.
But we don’t, instead we peel oranges and then sell them in plastic containers at the grocery store.
If we were talking about making hard trade-offs between preservation required to save lives and reducing pollution that would be one thing. Instead we use it to enable greater waste.