A Cleaner, Greener Future: ‘We are Key, and we are Responsible’

Amanda Jasi speaks to Nobel Prize winner Frances Arnold about how chemical engineering can help humanity survive and thrive

FRANCES Arnold is a chemical engineer and a winner of the 2018 Nobel Prize in Chemistry, awarded for her work on the directed evolution of enzymes. This technology has offered a route for making more environmentally friendly products including biofuels, detergents, and drugs. At the California Institute of Technology (Caltech), US, she leads a research group focusing on evolutionary protein design and using laboratory results to explain principles of biological design.

Arnold started on her chemical engineering career path achieving a PhD at the University of California, Berkeley, US. She initially studied mechanical and aerospace engineering at Princeton University, before working in solar energy.

What do you think is the key ingredient to your success?

“I’ve had a lot of luck, that always pays off. But I also know how and when to jump on new opportunities, and I’m not afraid to try new things. Sometimes they don’t work out so well, so I go on to the next one. But I’m not afraid to give something promising a go.”

Why did you transition your career to pursue chemical engineering, and what continues to motivate you?

“I moved into chemical engineering from mechanical and aerospace engineering because I was interested in renewable energy, particularly fuels from biomass. I ended up at Berkeley for graduate work, right at the beginning of the DNA revolution. That was so exciting; Genentech was going public, and other biotechs were starting up. I couldn’t think of a more exciting place to be at that time.

“I ended up doing my PhD with a professor who was building the engineering foundations of the biotechnology industry, and that was Harvey Blanch. During my PhD on protein separations, I learned about enzymes, and molecular biology and, particularly, how chemical engineers could be engineers of the biological world. Leading professors like Jay Bailey and Mike Shuler were using tools of molecular biology to engineer and modify microbes. I decided that’s what I wanted to be, an engineer of the biological world, only I was going to engineer proteins.

“What I continue to love about chemical engineering is that it changes all the time. Chemical engineers are at the cutting edge of translating advances in basic science to solving real-world problems. Science moves quickly, technology moves quickly, and so do chemical engineers.”

You were awarded the Nobel Prize in Chemistry for your work on the directed evolution of enzymes. How did your background in chemical engineering contribute to this development?

“I came into protein engineering, which was mostly done by structural biologists at the time, as an engineer, with the mind of an engineer. I first thought that I could engineer proteins the way they were going about it, which is, you get the structure and then with your big brain you figure out what pieces need to be changed. Then you go in and make those changes. I quickly realised that even though engineers can design airplanes and spaceships, no one knew how to design an enzyme, and least of all me. I turned then, with this engineering mindset, to the process by which all these remarkable catalysts of the biological world come about in the first place, and that’s evolution. Evolution is a wonderful, highly effective optimisation process on a multidimensional fitness landscape. Biology is, in fact, the best engineer of all time.”

How has digitalisation helped in your work?

“For the last 12 years now, we’ve been using machine learning to guide evolution in the laboratory. Evolution is beautifully tuned for enhancement by machine learning because we generate a lot of data, and with data you can learn what works and what doesn’t. Evolution herself is blind, she works only at the level of function. But if you add machine learning on the data – as we and others have shown – you can speed up the process. And some day the experimental part will be much smaller than it is now. That’s the whole goal, to minimise the number of experiments you need, maybe even someday do the evolution all in-silico to explore this vast space of possibilities.”

How are evolved enzyme technologies contributing to solving grand challenges now, and how do you think they could further contribute?

“Evolved enzymes are supporting the conversion of plant-based materials to jet fuel, they’re reducing the energy needs in washing machines, they’re making many industrial processes more environmentally friendly, they’re used to cleanly make pharmaceuticals, reducing waste tremendously. And we’re still at the very beginning of this field, where we’ll be able to use biology’s very clean collected chemistry and ability to use bulk environmental materials, like carbon dioxide, to make what we need and transition away from fossil fuels.”

More broadly, how else do you think an evolutionary systems approach can contribute to solving challenges?

“Engineers don’t have a single design algorithm that works at all scales, but biology does. There’s a single process that works from molecules to whole ecosystems, and it’s called evolution. I applied it to enzymes but I’m pretty sure in the future people will be able to apply evolutionary design principles to whole metabolic pathways, genetic circuits, organisms, and ecosystems, they just have to figure out the right tools for doing that. It’s only limited by the creativity of future engineers.”

What would you say to chemical engineering undergraduates or recent graduates wishing to enter your field of research, especially young women?

“I would say it’s never been a better time to be a chemical engineer, because to solve the world’s problems we need all the good brains – 50% of the good brains belong to women – and we need good hearts. We need people who care about our planet, to make sure that we can survive and thrive.”

How do you think we as an engineering community can best engage with a diverse range of children and young people to inspire an interest in engineering?

“Young people, from what I’ve seen, want to improve the world. They don’t want to take the world as it’s been given to them, they want to make it better. We need to demonstrate how our work as engineers helps people and helps the planet – not just make a profit. I also see that young people want to enjoy their work, especially in teams, but unfortunately much of the education that leads up to engineering is still not well-suited to this. So, some careful thought about how to train people for this rapidly changing world, where we work in teams on important problems, is important for our field.”

How do you believe chemical engineering can play a role in the next ten years to help deliver the solutions society needs to address global challenges and allow survival?

“It’s pretty obvious that chemical engineers must be responsible for greening of chemical processes. We have to be responsible for making better foods, providing clean water, tackling climate change. In the past, chemical engineers mainly worked in the fossil fuel industries, or for chemical companies that converted fossil feedstocks into chemicals and materials. But now the profession has broadened dramatically and we’re leading the transition to clean energies, clean food, clean agriculture, and clean chemistry.

“We make things. We make all these things, and we’re responsible for doing it better.

“We are key, and we are responsible. We must.”

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Frances Arnold and Robert Langer spoke to The Chemical Engineer as part of a campaign for the Engineering Heroes film series, launched by the Royal Academy of Engineering in partnership with Amazon and Becoming X: https://www.thisisengineering.org.uk/latest/heroes

Read the Robert Langer interview here