Unraveling DNA to transform carbon with Ariel Furst

Kara Miller:  I’m Kara Miller.

Rob Stoner: And I’m Rob Stoner.

KM: And from the MIT Energy Initiative, this is What if it works?—a podcast looking at the energy solutions for climate change. Today we talk to a serial entrepreneur who insists sustainable alternatives do not have to be that complicated.

Ariel Furst: A lot of people expect technology to be very fancy and therefore very expensive. And so, when you see simple solutions, people often overlook them.

KM: That’s Ariel Furst, a professor of chemical engineering at MIT. She’s the co-founder of multiple startups.

AF: And so that’s one of the challenges that we face in our research, is people say, “Well, it’s so easy. Is it really this technological advance?” And we say it is because it’s accomplishing what we want to accomplish, just without hundreds of millions of dollars of infrastructure required.

KM: In a minute, we’re going to talk about talk about athletic wear, believe it or not, but before we do, the key to lots of Furst’s environmentally-minded breakthroughs is something pretty small. Actually, it’s very, very small.

AF: My research has always been at the intersection of engineering and biology, and I think people often underestimate what biology can do. So my lab looks a lot at the natural environment and the microbes that are there, and they can do pretty much any chemical process that we want to do, and that chemical engineers have been working for hundreds of years to try to accomplish, but they can do it more efficiently and in a living organism that can also stay alive while it’s doing that. So, if we look to those systems that have this head start on us through evolution, then we can come up with simpler solutions.

KM: Which brings us to athleisure and a conversation that Furst had with one of her undergraduate students.

AF: One of them was telling me about waste in the U.S. And the average person in the U.S. throws out about 80 pounds of clothes a year. And almost all of that is polyester. So we got to thinking, well, is there a way for us to help with this problem? There are places in the world now, especially in the Global South, where you can’t even see the ground because there’s so much textile waste.

KM: But the waste is not coming from the Global South, it’s coming from the Global North, from places like the U.S.

AF: And when you donate your clothes or when you recycle your clothes, that’s where they often end up. And so then they’re either burned, which is releasing toxins into the air that these people breathe, or they’re left to degrade slowly on land. And again, this ties back into our goal of equity. It’s really inequitable for people in the Global North to be heavy consumers of these products and then ship them off when they’re done to be someone else’s problem.

KM: And many of those clothes are made out of plastic-based fabrics, like polyester, like spandex. So if you break them down, you encounter a new set of problems.

AF: So one of the challenges we see with a lot of plastic recycling is that when we do it with current methods, we end up with microplastics. And these generally end up in the ocean or in drinking water or in food systems and the health effects of them aren’t totally known, but they’re probably not great. So our goal was to figure out how we can take these polyesters—these things that they make most of the fast fashion clothes out of—and turn them back into things that companies would want to use. Then we can basically circularize the fast fashion economy so you’re not generating more of these starting materials that generally come from fossil fuels and you’re instead recycling it from these clothes.

KM: And Ariel Furst and her students figured out a way to do it. How?

AF: So this was actually inspired by a technology that we had in the lab. And we were thinking about ways we could better use it, which is basically our ability to just decorate microbes with these proteins that can do whatever we want them to. So we pick the right protein and it can do whenever task we tell it to. And the great thing is we can basically freeze-dry these microbes, so we can turn them into astronaut ice cream if you’ve had that or if you see the freeze- dried fruit.

KM: It’s not that good, but…

AF: But it works really well for killing the microbes, but keeping these proteins active. So we end up with this really light powder that is very, very active, and that means we can make kilograms of this stuff for dollars. And so it really decreases the cost of protein materials, which has been one of the challenges in bioengineering. And so we were thinking about what we think these would be great for and the great thing is even synthetic clothes have a lot of chemical bonds that look like chemical bonds in our bodies. And what that means is that there are proteins out there that can chew up those bonds and split them. And, so, we went searching for some proteins that can do that. We found some and we were able to kind of decorate cells with them and we found that the can chew up polyester, the synthetic material, very, very quickly.

RS: So this is what I like about your style. Again, you’re not solving the naive problem that would come to mind at first. Eat this stuff, make it go away. It’s turn it into something we can use and recycle it and create a loop. And that’s sort of the definition of sustainability, I think.

AF: But again, this is not coming from me. This is coming from the high schoolers and undergrads that we work with who say things like, well, most people, when they do plastic recycling, if they’re doing it kind of to the end product, it ends up as CO₂. So how are you really solving a sustainability problem if you’re generating CO₂?

And so we were thinking about how we can kind of bypass that step. It’s really hard to change people’s behavior, right? So instead of asking people to potentially not shop at their favorite stores. We’re making decisions that would allow them to do things in a circular way. You know, there’s a lot of industries that are not gonna be able to be decarbonized, especially in the near term. So what can we do to stop generating more CO₂ and maybe take some of those emissions and use them to generate starting materials again to circularize these economies?

KM: Okay, so when you have that shirt that like nobody wants anymore and it’s made of polyester, and then you unleash the microbes and they eat it and you like hold up this test tube and there’s like a little liquid in it, right? And it’s like, this is all that’s left of the shirt. What is that? What is in that test tube?

AF: So that is what’s called monomer. So that’s the small chemicals that they make these polymers out of, which is just the fancy word for the things they make the thread that makes polyester out of. So they’re just the polyester starting materials. So the great thing is, especially for polyester specifically, is those molecules look like things that microbes in soil eat. So in addition to being able to use these for chemical recycling, you could also just use them as kind of feedstock for microbial processes.

RS: So where’s the catch? How come we’re not using this? Or maybe we are?

AF: So the catch right now is most of our clothes are not just polyester. So what we’re working on now is making more of these astronaut ice cream materials that have different proteins on them so that you can throw in a mix of things to degrade whatever mixture of waste you have.

RS: Okay, I see, so you don’t have to sort the clothes, which would be an expense.

AF: Exactly.

RS: You get smart.

KM: So what is in clothes that microbes, that you don’t yet have the microbes to eat?

AF: So things like nylon is a pretty prevalent one, especially in athleisure, or elastin, which is what’s in all the stretchy athleisure material. When you look at them, often they have mesh panels or things like that that are different materials. And so you have to be able to chew up all of it.

KM: I guess there’s sort of two things you could do. One is like the whole cycle, as you say, you could degrade a shirt and then you could have maybe the building blocks to make a new one so you don’t have to use petroleum, as you said, to like do it again. But it also seems like even if you can’t sell a company on like, let’s go full cycle, like let’s do this, you could at least say this is better than throwing it in the trash can, then chopping it up into little bits, as you say, in like microplastics and they’re wherever. At least to totally degrade it and then throw that, what was in the test tube away, is far better, right, than what we’re doing now.

AF: Yes, definitely. And one of the things that is really fantastic about this is you don’t need any chemicals to do this degradation. So in addition to thinking about chemical engineering, scaled processes where you would have this in a large reactor or whatever, can we use things like at home composters where you throw in our microbes and some water with your clothes? Because that’s all we need to do the degradation. So if you can do that, then you could do it at home. You wouldn’t have to ship your clothes off to be recycled.

RS: But what happens when you get these bugs out all over the place in everybody’s homes, and the bugs get out and they eat my clothes?

AF: So the great thing is these bugs are dead. So we’re not worried about them kind of being an invasive species, which is a valid consideration when you think about engineered microbes. But because we kill them, turn them into astronaut ice cream, that’s not an issue. And so we’ve engineered them to basically turn on at high temperatures. So at temperatures that most people aren’t wearing clothes, you know, we’re talking almost boiling water.

KM: So unless you’re wearing your clothes in the deep sea vents…

AF: Exactly. So then we can kind of control when these microbes turn on.

RS: How do you, how do you engineer something to be that tough?

AF: Lots of talented students.

RS: Well, as you know, I’m a total moron when it comes to DNA. From our past conversations, I’ve pointed out to you that the DNA you’ve used in some of your approaches is too fragile to be used in the way you’re planning to use it. But you’ve pointed it out to me that it’s not.

AF: People underestimate DNA, I think, and, you know, with a lot of the current tools we can use for engineering microbes, we can tune them with very high precision. And for these proteins, we could tune very specific pieces of the protein, as well as kind of the whole microbe itself, so how many of these proteins we’re putting on the surface, how stable they are is impacted by that, kind of how they’re connected to the microbe itself, and that impacts how hot we can turn up the sauna on them basically.

RS: So give us an example, if you can, of how you’ve done this. What sorts of applications does this find its way into?

AF: Yeah, so we think a lot about circularizing economies and one of the main ways we look at that is with critical materials. So there’s lots of things that we’re now realizing we need a lot more of to make things like solar panels and batteries, even batteries both for your car and for your cell phone and your smartwatch. And we’re not very good at recycling those battery materials right now, but we’re going to have to start if we want to use batteries more. And so we’ve also been able, just like we can put proteins on microbes that chew stuff up, we can put proteins that specifically grab stuff from pretty complex mixtures. So say you have a ball pit, you only want the yellow balls. We can put a protein on there that only grabs the yellow ones and leaves all the other colors. And so that’s basically what we do with these metals that are those critical materials.

RS: That sounds like it’s mimicking the biological use of DNA to gather together strands of proteins.

AF: Yeah, so these are basically the DNA we’re using to tell the microbe what to do. So here, we’re using DNA to basically program. And then in some of our other work, we do use DNA more as a material, but here we’re using that to tell the microbes to make proteins that we then use as kind of like the claw toy.

KM: Is the idea there that you’re recycling a battery, it’s got a mixture of metals in it, and you’re trying to say, well, this is this metal, and you trying to sort them so that you can then take that pure thing and say, OK, well what are we going to use pure lithium or whatever for again, instead of it being a jumble of other things?

AF: Yes, exactly. And right now, the way people do that, people have come up with very sophisticated chemical tools to do that. But they’re often very energy intensive. And this is another example of where evolution, you know, these proteins come from these microbes needing one specific metal and not wanting anything else. And so they need to be able to grab that one metal and nothing else. So if we take those proteins and use them, we can get that same specificity that it’s nearly impossible to get right now chemically.

KM: When I think about clothes companies and the sort of appeal that they make to people and the environmental impact that they would like to have, like, I would think that if they knew anything about what you’re doing, which they might not, but you could get companies to make, let’s say, simpler leggings that didn’t have mesh panels and say, like if you buy this legging, you don’t have to, we make the ones with the mesh panels or we do this or that, but if you buy the like plain black polyester something something, because it’s simpler, look at the awesomeness that we can do with this. And people might be like, well, they’re like all about the same price. Y’all do the thing that seems green.

AF: Yeah, I mean, that’s the goal. And at least in Europe that’s going to be the direction everything’s heading. So there are some mandates in the EU that are going to make all clothing have to be made of a single material. Basically they’re doing it to improve existing recycling processes so that you can recycle more clothes, but it would significantly help us kind of, if you could have single stream.

RS: Are they doing it specifically to enable you?

AF: No, no, definitely not. That would be fantastic. But this is existing recycling technologies generally depend on very pure feedstock. So very pure input. So you can’t have these mixed materials. You can’t have those leggings with that mesh panel. So just to use current methods of recycling, they’re making this a mandate that you have to use kind of single types of fabric.  

KM: Has anybody come to you, a government or a company, and said, like, this is, yes, we’d like to do this?

AF: Yes, so we’ve had some really fantastic interactions with groups that have made documentaries about textile waste. They’re very passionate about solutions to that, right? They don’t want to just educate people on the waste. They want to help solve that problem. And so we’re working with them to get access to some of these textile dumps in the Global South and so that we can try once we have these mixtures of microbes to degrade mixed textiles and help clean up the environment there. Without needing to burn the clothes, which is what happens now.

RS: How does that pay for itself? Does the government have to provide the funding to do it? Are you making a useful product somehow?

AF: It honestly will depend a lot on clothing/chemical companies, because if they start to see value in these starting materials that aren’t from fossil fuel feedstock, so they may be a little pricier, but they’re not going to be orders of magnitude price here. They’re not gonna be a hundred times pricer. Then they can purchase these and it would be useful for them because then…

RS: And create a loop.

AF: Exactly.

KM: As I mentioned at the beginning of the show, Ariel Furst is not just an entrepreneur. She’s a serial entrepreneur, and her efforts to create a greener world extend to another company of hers, Helix Carbon, which also taps into her love of biology.

AF: Helix carbon is inspired by the DNA helix. We talked a little bit about how DNA is the genetic code, right? It can help cells program making proteins, but DNA is this three-dimensional material that has really cool properties beyond just the letters of the bases.

KM: DNA has two strands that unite in a specific way, Furst says, and the two strands are brought together by hydrogen bonds which are not particularly strong.

AF: And that works almost like Velcro or like a zipper coming together. These two things that are floating separately, they come together very tightly, but it’s also reversible. And so this allows us to use DNA to regenerate things.

KM: What Furst is looking to do with this DNA is to help facilities that generate a lot of carbon dioxide use it in a way that’s helpful to them. And that means turning it in to all sorts of useful products.

AF: Plastics, paint, liquid, aviation fuel—and these are things that people called tough-to-decarbonize industries, because it’s gonna be really hard to make a plane fly on solar power alone right now. So these are the things that are gonna take longer to fully reach an energy transition. And so until then, we can at least make their process net zero, right? Because we’re pulling CO₂ out to be the start of that process.

KM: So how do you use the CO₂ that facilities emit in a more effective way than it is currently being used? Furst says, what Helix Carbon does is it makes synthesis gas, also known as syngas.

AF: It’s a mixture of carbon monoxide and hydrogen. Right now it costs about $700 a ton if you get it from fossil fuels. Costs about $1,200 a ton minimum to get it from electrochemical processes. So, people don’t want to use it because it’s not sustainable or profitable for their company, right?

RS: Don’t want to use the electrical process.

AF: Yes. Yeah. So we have been able to basically stick our catalysts onto one strand of DNA, stick the other strand of DNA on a carbon electrode, which decreases the cost of our system. And that decreases the amount of energy we need by about 30%. And it brings the overall cost per ton of syngas to about $350. So it’s win-win because it will actually incentivize companies to capture their CO₂ and convert it into something they can actually use.

RS: I guess syngas is the main input to Fischer-Tropsch process for making hydrocarbons.

KM: So, okay, so this is a gas that’s already being used and the Fischer-Tropsch process that would be used to make things that like could power a big ship to go across the ocean or something, right? So there’s already a need. So what you’re trying to do is just say like, don’t use this, use this other way of making it. It’s better for the environment and you’re trying to make it cheaper.

AF: Yes, and it can all be done on site. So now a company would install our system, it would capture CO₂ that they’re already emitting, and turn it into syngas right there in a shipping-container-sized unit. Syngas prices are pretty strongly tied to natural gas prices, and so as those fluctuate, so does company costs. And so now they know exactly what their cost will be long term for syngas.

RS: So you can participate in futures markets very efficiently.

AF: I guess. That’s not… That is beyond my area of expertise but people can with this tech.

KM: And are there many companies that are doing both things? They’re emitting CO₂ so they’d be a good candidate for capturing it and wanting syngas?

AF: Yes, most kind of chemical plants right now use syngas for at least one of their processes. And so most conventional chemical factories could use this technology, probably, for them to do it.

KM: And they’re also big emitters?

AF: Yeah.

RS: So this just sounds to me like an incredibly valuable company. You’ve got, it sounds like a lock to make all of the sustainable air fuel, all of the e-diesel, all the e-gasoline, all have the E every fuel and from the way you’re describing it, companies that are in these businesses should be tripping over themselves to license your technology. Is that happening?

AF: Yeah.

RS: Or do they need to hear this podcast?

AF: We already do have a lot of interest from pretty large kind of chemical companies, and it’s very exciting because we do see a lot of external interest from people who are just interested in sustainability. So we won the Climate and Energy Prize. It was $100,000 in non-dilutive capital. Plus what was very exciting is the $5,000 audience choice award. And so that was really gratifying for us to see that this was impactful and meaningful to not only the judges in the large petrochemical companies, but also to the general audience who were listening to all the pitches.

RS: So without screwing up your access to dilutive capital, the kind of capital you’re really gonna need to go big on this, where’s the catch?

AF: Actually, there is no catch.

RS: There’s no catch, well said.

AF: That’s my challenge. People ask me that and I just, the great thing about the DNA we’re using is it’s synthetic DNA, so it’s chemically made. So it’s not like we’re taking DNA from any sort of biological thing. And it’s very inexpensive. It means we can use significantly lower amounts of catalysts, so the expensive metal parts of this, and we can carbon electrodes that are much more sustainable and less expensive. So it really also decreases the overall cost of these systems to enable their broader use. So obviously we’re targeting these large petrochemical companies, but this could also be useful for turning things like solar power into chemical storage. Cause if you can make that solar energy go into one of these system to make things like ethylene, you then have something that’s chemically stored energy.

RS: So what’s the advantage here for the developing world where you have a lot of interest? I mean, how do they benefit from this uniquely or especially?

AF: Because these systems are very inexpensive and they can run off of systems that don’t require a power grid. You can set these up pretty much wherever you want.

RS: What’s these? These are a syngas-making machine?

AF: So syngas is our initial target, but we also have catalysts that can make things like ethylene and so that’s good for chemical energy storage, because then you can use that either for plastics or burn it directly and so in a lot of places that don’t have grid connections, so where solar or battery storage is a challenge, this would allow them to basically capture energy from clean systems and keep it in chemical energy.

RS: So ethylene is a fuel, is it a useful fuel or can you get to a useful fuel by the same sort of logic?

AF: Yeah, so we can take that and make it into longer chains, so liquid fuels. You can also use ethylene directly and burn it. It’s not the most efficient, but it is a source of chemical energy.

RS: So you could imagine one of your plants sitting in some village in West Bengal.

AF: That is the goal. Powered by a solar panel.

RS: Cool, I want in.

KM: I mean, a lot of the stuff you’re doing that we’ve talked about, you’re kind of on this path to commercialization. When things come out of the lab and then you’re hoping like, oh, you know, we can like change how we deal with athleisure pants or whatever. What are the biggest hurdles that you hit? Is it like, it’s hard to get people to invest? It’s hard get people understand the technology? I don’t know. You know, what’s the hardest thing about going on that path from like the lab to the marketplace?

AF: Honestly, within the MIT ecosystem, it really hasn’t been difficult. Of all the places I’ve been, MIT is really very strong for that. So for Helix Carbon, I was actually approached by two MBAs who were interested in commercializing this. They had heard about it in one of their classes. And their goal in coming to Sloan for an MBA program was to find a sustainable tech to commercialize. And so I feel like I get a lot of support in the areas that I’m not as comfortable with as kind of engineering faculty, so they do the business plan, they do all the customer discovery work, they build their network, and they’re even the ones who are going to be doing the actual fundraising, so pitching to VCs and all of that, and so having that as a resource I think kind of circumvents a lot of the main challenges with technology commercialization.

RS: You’ve been involved in a program that was set up by our former, former president, the great Susan Hockfield, who’s a dear friend, called “Female Faculty Entrepreneurs”, FFE, is that right?

AF: I think they’ve changed the name now to Faculty Founders, but yes, it’s the same program.

RS: So how does that work? And is that what you’re talking about when you’re when you talking about how easy it’s been?

AF: Yes, so that is a fantastic program that was basically set up through the School of Engineering to train female faculty on how to be entrepreneurs because female faculty at MIT start companies at one-tenth the rate of male faculty. So the thought is that that leaves a lot of tech on the table that should be commercialized. And the thought between Susan Hockfield and Sangeeta Bhatia, who was one of the other people running the program, was that a lot of this is just because of lack of exposure. And so it was to kind of train us. We got industry mentors. It helped build a network of other faculty on campus that are interested in commercialization and it’s been really useful. It also connected me to a lot of the student entrepreneurship programs which have helped my students think about their technology and also to some of these MBA students who have helped us commercialize.

KM: And so the bigger question, what do you feel like are the challenges ahead or how hopeful do you about the trajectory we’re kind of on in terms of energy usage? Obviously, we’re really trying hard to keep the global temperature in check.

AF: Honestly, I feel very positive about the way sustainability technology is moving. And a lot of that honestly, as I’ve mentioned this a couple of times, but it’s the high schoolers and undergrads that work in the lab. They are incredibly determined and mission-driven to make the world a healthy place for everyone. And so they are the ones driving a lot of our motivation and the actual translation of this tech and making sure what we can do is actually usable, and cost effective, and transportable, accessible. So I really have to give credit to them for that.

RS: You mentioned to me that you were thinking about ways to destroy these so-called forever chemicals, PFAS, PFOS, those sorts of things. Is that really gonna be practical, do you think, using these techniques?

AF: It has to be, right? We need methods to degrade these chemicals that don’t also impact the environment. A lot of the chemical strategies to de-grade forever chemicals involve more PFAS, involve more of these chemicals, because that’s what captures them best.

KM: And these are chemicals that are unleashed by, like have been in plastic, and then gets unleashed over time?

AF: Yeah, these are non-stick cookware in the northeast. They’re also on a lot of the military bases and a lot of the firefighter training sites because that’s what’s used in firefighting foam.

RS: Also, dental floss, like what are they thinking?

KM: Wow. Okay.

RS: Stuff you put in your mouth.

KM: Okay, and this stuff hangs around in water and in the ground and stuff, and so you’re trying to…

AF: We’re trying to destroy it, yeah. With microbes.

RS: This has become a major priority for a lot of companies that produce chemicals of various kinds because it’s just getting everywhere.

AF: So the great thing about evolution is if you look at a lot of these sites that have very high levels of these chemicals, there are microbes growing there. And the way they’re growing there is by evolving to eat these compounds, these chemicals. And so, you know, by pulling out the proteins that are responsible for that and kind of putting them on our microbes, on our astronaut ice cream microbes, we can at least start to degrade these and make them either to the point where they’re no longer potentially harmful for humans or animals, or just fully degraded.

KM: That’s amazing. It’s like the upside of the downside of like, you know, there’s these like the Pacific Garbage Patch and all this stuff and you think all this terrible, but then like, I guess somewhere there’s like some little organism that’s like, I could eat this. This is pretty tasty.

AF: This is why I think, and I’m going to get a lot of flak from my lab and my family for saying this, but microbes are the coolest, because they have found microbes living in gold mines and abandoned gold mines, that have basically shifted all of their metal usage to gold, because that was what was abundant. And you can pretty much find that in any environment that is non-native. The microbes there have evolved to use what’s around them.

KM: Ariel Furst is professor of chemical engineering at MIT. She’s also the co-founder of two companies. Ariel, thanks so much for being here. This was great.

AF: Thank you so much. This was really fun.

RS: Thanks, Ariel.

KM: What if it works? is a production of the MIT Energy Initiative. If you like the show, please leave us a review or invite a friend to listen. And remember to subscribe on Apple Podcasts, Spotify, or wherever you get your podcasts. You can find an archive of every episode, all of our show notes and a lot more at energy.mit.edu/podcasts and you can learn more about the work of the Energy initiative and the energy transition at energy.mit.edu. Our original podcast artwork is by Zeitler Design. Special thanks to all the people at MITEI and MIT who make this show possible. I’m Kara Miller.

RS: And I’m Rob Stoner.

KM: Thanks for listening.