[gentle music] - [Host] The Pacific Garbage Patch, the collective name of a swirl of floating plastic trash that drifts in the middle of the Pacific Ocean.

The floating island of junk is now twice the size of Texas, and it's mostly a massive plastic, plastic bottles, wrappers, containers, and fishing nets, and even tiny pieces of plastic called microplastics.

You name it, if it's made of plastic, it's probably in there.

Nature can't break any of it down, but only make it smaller.

That's where microplastics are created, and all of it, large and small is lethal to fish, wildlife and people.

- Most materials that you find in nature, nature's had millions of years to figure out how to break down.

Plastic's only been around for a hundred years at most.

- [Host] Much of this garbage is made up by a type of plastic called PET or polyethylene terephthalate that you might find in things like water bottles and other packaging.

But what if we found something in nature that could actually eat some of it?

- In our lab, we've taught this microbe that couldn't eat plastic, how to eat plastic.

[gentle music] - [Host] Crook and colleagues at NC State are using an enzyme found in Japan, where in 2016, researchers announced they had found some bacteria years before there was slowly eating away plastic bottles in Osaka at a recycling facility, and they had been trying to make the process go faster.

Experiments around the world had worked somewhat in the lab, but one challenge was getting it to work well in salt water.

Well, these scientists think they may have come up with a way to do that.

Well, what is this new way?

It might help to look at the bacteria that produces this special enzyme microscopically.

- [Nathan] What you're seeing are actual images of Ideonella sakaiensis.

This is the microbe that was discovered by researchers in Japan.

This is the cell body of the microbe, and it's actually adhering to this surface of a plastic, the plastics on the bottom there.

And what's interesting about this plastic is that if you take the bacteria away, it looks pitted.

There's holes in that plastic where that microbe has eaten it away.

[gentle music] - [Host] Crook and Tianyu Li are hacking this Japanese plastic-eating enzyme, putting it into a bacteria called Vibrio natriegens, which is a super fast growing bacteria that thrives in salty environments like the ocean.

- This strain is actually the fastest growing microbe that we know of.

- [Host] When they inject their hacked enzyme into the super bacteria, flagella at its tail helps it swim toward the plastic molecules using enzymes they say are displayed on top, which are ready for eating.

They call what's going on here, hitchhiking.

For the experiment, they first grow their bacteria into nutrients, and once that's done, they add a sample of their PET plastic and it ends up looking a bit like, well, cooking broth.

[gentle music] - So you're start, you've prepped everything.

What are the next steps at this point?

- So next step, while mixing the PET microplastics into the cell culture.

- So wait, hold it.

Hold that up a little bit.

Looks kinda like goo.

I mean, what actually is ultimately in there now?

- [Tianyu] That's a really great question.

So inside of the shake flask, it is a Vibrio natriegens bacteria cell, which has been engineered to displaying relevant enzyme can depolymerize.

- [Host] So an enzyme that can depolymerize.

So PET like water bottles and whatnot.

- [Tianyu] Polyester, clothes, fibers.

- Okay, so we've got our goo, where are we taking it now?

- So what are we gonna do next, we'll be putting the shaking flask, holding the reaction into the shaking incubator to make the reaction happening at a stable temperature and shaking speed.

- Okay, let's go ahead.

- So what are we gonna do is open the shaking incubator door and plug it, put it into the rack.

- [Host] Li says it'll take several days for this shaking incubator to drive the reaction with a modified bacteria degrades the PET.

And once it's finished, it only takes about 20 minutes to verify the reactions of work.

The sample is typically around 10 microliters, which is certainly not a huge amount, but that's why the research is so important, since it may have big potential in getting rid of PET, which makes up about 12% of all plastic around the world.

But this all begs the question of, after the enzyme is degraded the plastic, what's left?

- [Nathan] It's broken down into two particular molecules, one's called ethylene glycol and one is terephthalic acid.

Luckily, both of those molecules nature knows how to break down.

So we can then take those molecules and use them to feed microbes, potentially using those as feedstocks either for new plastics or for producing fertilizer, for example, or biofuels or biodegradable plastics.

- [Host] So the result is the bacteria keeps growing as long as the plastic food stock lasts.

It's almost a closed loop process.

Crook says that one day he hopes one could throw a simple packet of the solution into a vat with unwanted PET plastic and get rid of it.

But he cautions, there's still well in the research phase.

And while their process breaks down PET, there are lots of different types of plastic and each one of those will need a different biological strategy to get the job done.

- All of these plastics are chemically different, and so they require different enzymes to break them down.

That's why there's actually a large global community of researchers trying to make enzymes and microbes that can break down all the different types of plastic that are an issue in the environment.

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