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Newly discovered deep-sea enzyme breaks down PET plastic

phys.org

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Re: Newly discovered deep-sea enzyme breaks down PET plastic

#41

Post by ZeWaka »

digging wrote: post #36
hutzlibu wrote: post #29

Earlier quoted context omitted.

"Currently, recycling plastic is a bit of a lie -- very little of it is actually recycled." Depends where you live and what you consider recycling. If you mean, making new plastics out of the old, than the challenge is, that there are many, many different plastics you cannot just melt in and reuse if mixed together. A annoying, but working solution here in germany is a mandated bottle bill. Meaning you pay 25 cent ex…

> And for the rest, the most pragmatic solution is burning it for energy. I really wish we'd do more of this. I know it's not ideal, but we in the US need to treat plastic like the trash that it (mostly) is. And trash is just fuel. Instead we have convenient single-stream recycling which means all our actual recyclables also end up in the trash and/or oceans.

We actually do a fair amount of this in the US. Marion County in Oregon burns 90% of their trash. It's much better than landfills, anyways.

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#42

Post by hinkley »

pneumic wrote: post #8
gilleain wrote: post #3

Slightly misleading headline, as PET (polyethylene terephthalate) hydrolases were already known - see https://www.chm.bris.ac.uk/motm/PETase/PETaseh.htm This is a study of an archaeal enzyme (from the deep-sea) that can degrade both long-chain and short-chain polymers that is more efficient at 70 deg C than other enzymes. The details are that this is a feruloyl esterase with a conserved alpha/beta-hydrolase fold but…

Yeah, it's not bad news at all but it appears to be one of many that still require considerable heat, industrial infra, etc. Has anyone attempted to put these enzymes to the test in at some scale in an industrial setting, I wonder?

I mean my processor hits 70° and has for a decade or more, and my car engine thinks 87° is the happy temperature.

70° is maybe a little out of the reach of a home system but nothing for a municipal system. Right?

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#43

Post by aftbit »

zellyn wrote: post #40
lanstin wrote: post #32

Earlier quoted context omitted.

Unlike the plastic substrate of modern technological society, plants have survived hundreds of millions of years of efforts by the rest of the biosphere to eat them.

True, although I believe dredging up unusual enzymes from the stygian depths facilitates new and exciting dystopian storylines.

You might enjoy the Rifters trilogy by Peter Watts.

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#44

Post by gruez »

hutzlibu wrote: post #29
multiplegeorges wrote: post #6

So dumping all our plastic in the sea will work out! /s It seems like these discoveries are coming quickly and in higher numbers. Maybe there's hope in recycling/processing plastics down simpler molecules after all. Currently, recycling plastic is a bit of a lie -- very little of it is actually recycled.

"Currently, recycling plastic is a bit of a lie -- very little of it is actually recycled." Depends where you live and what you consider recycling. If you mean, making new plastics out of the old, than the challenge is, that there are many, many different plastics you cannot just melt in and reuse if mixed together. A annoying, but working solution here in germany is a mandated bottle bill. Meaning you pay 25 cent ex…

>And for the rest, the most pragmatic solution is burning it for energy.

No, burying is better because it sequesters the carbon rather than releasing it into the atmosphere.

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#45

Post by vagab0nd »

Max-q wrote: post #30

As much plastic as we dump into nature now, we increase the chance for a mutation of a microbe being able to digest it. If that microbe manage to multiply and spread, plastic can start to rot, just like wood is doing now. On a long term basis, that might be a good thing, but in the short term it would be a catastrophy. We are using plastic as a long lasting material, often with no surface treatment. Imagine if wire i…

Not to undermine your point about cleaning up plastic, but following your logic: isn't this similar to the antibiotics situation, just maybe on a longer time scale? The more you use it the less effective it is. What's the ultimate solution?

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#46

Post by gruez »

ZeWaka wrote: post #41
digging wrote: post #36

Earlier quoted context omitted.

> And for the rest, the most pragmatic solution is burning it for energy. I really wish we'd do more of this. I know it's not ideal, but we in the US need to treat plastic like the trash that it (mostly) is. And trash is just fuel. Instead we have convenient single-stream recycling which means all our actual recyclables also end up in the trash and/or oceans.

We actually do a fair amount of this in the US. Marion County in Oregon burns 90% of their trash. It's much better than landfills, anyways.

How is burning better than landfilling it? If the landfill is lined the garbage isn't going anywhere, and leaving the plastic in the ground is much better than releasing its co2 into the atmosphere. Land use might be an issue in some places, but I doubt that's the case in Oregon.

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#47

Post by dzdt »

The way to understand the origin of fossil fuel deposits is that hundreds of millions of years ago trees were made of plastic.

Thats not quite literally true but it gives the right sense. In the Carboniferous period trees grew abundently but there were not yet bacteria that could break down the lignins composing the woody structure. Its very similar to what you'd get with plastic trees today: they would fall and pile up like junk in a landfill. Then eventually this would be buried and result in the many-meters-thick coal deposits we find today.

Lessons? I don't know. But piles of un-decomposable hydrocarbons is not a new thing for the planet.

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#48

Post by yukkuri »

vagab0nd wrote: post #45
Max-q wrote: post #30

As much plastic as we dump into nature now, we increase the chance for a mutation of a microbe being able to digest it. If that microbe manage to multiply and spread, plastic can start to rot, just like wood is doing now. On a long term basis, that might be a good thing, but in the short term it would be a catastrophy. We are using plastic as a long lasting material, often with no surface treatment. Imagine if wire i…

Not to undermine your point about cleaning up plastic, but following your logic: isn't this similar to the antibiotics situation, just maybe on a longer time scale? The more you use it the less effective it is. What's the ultimate solution?

Walls and ladders. There isn't a solution to evolution, you just have to keep adapting.

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#49

Post by hutzlibu »

gruez wrote: post #44
hutzlibu wrote: post #29

Earlier quoted context omitted.

"Currently, recycling plastic is a bit of a lie -- very little of it is actually recycled." Depends where you live and what you consider recycling. If you mean, making new plastics out of the old, than the challenge is, that there are many, many different plastics you cannot just melt in and reuse if mixed together. A annoying, but working solution here in germany is a mandated bottle bill. Meaning you pay 25 cent ex…

>And for the rest, the most pragmatic solution is burning it for energy. No, burying is better because it sequesters the carbon rather than releasing it into the atmosphere.

If it means not burning coal, oil or gas instead and there are good filters, I think burning plastic makes sense. But if you can actually get all the needed energy from non fossil sources, then yes, burying makes more sense. But I think only some rare places on earth are that far.

Re: Newly discovered deep-sea enzyme breaks down PET plastic

#50

Post by Intralexical »

yukkuri wrote: post #48
vagab0nd wrote: post #45

Earlier quoted context omitted.

Not to undermine your point about cleaning up plastic, but following your logic: isn't this similar to the antibiotics situation, just maybe on a longer time scale? The more you use it the less effective it is. What's the ultimate solution?

Walls and ladders. There isn't a solution to evolution, you just have to keep adapting.

Is it feasible for something like, e.g., teflon to be decomposed biologically?
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