Inspired by the biological processes that drive natural selection, Caltech biochemical engineer Frances Arnold launched a field called "directed evolution" and revolutionized the way researchers design more effective drugs and create cleaner industrial processes.
This week, Arnold's pioneering work was recognized with a Millennium Technology Prize, making her the first woman to win the prestigious award. The prize is awarded every two years by the Technology Academy Finland and comes with $1.1 million in cash. Previous winners include Linux creator Linus Torvalds and blue LED inventor Shuji Nakamura, who went on to win the 2014 Nobel Prize in physics.
Arnold began her career in renewable energy, and she has spent a lot of time thinking about the damage humans are doing to the environment. By mixing up DNA in test tubes and putting it into microbes that pump out specialized proteins, she aims to create cleaner, more environmentally friendly methods to make the products we use every day.
The 59-year-old mother of three draws from many fields to do her research, and consequently has been elected to all three branches of the National Academies of Sciences, Engineering and Medicine — the first woman to achieve this rare feat.
The Times caught up with Arnold on the night before she received the prize in Helsinki, Finland, to discuss her groundbreaking work.
You started off as a mechanical engineer. How did you make your way into biology?
I was employed at the Solar Energy Research Institute in the late '70s when Carter was president, and as a country, we had a goal of renewable energy development. Novel idea, huh? But then Reagan was elected, and then the political climate changed a lot.
I decided to go back to college and get a PhD — only this time I wanted to do it in the emerging field of biotechnology. I made a small switch from mechanical to chemical engineering and started learning some biology, and fell in love with engineering proteins.
What drew you in?
Engineering the biological world was even more interesting than engineering the mechanical world. Because to me, nature is the best engineer — having created, over 4 billion years of evolution, some pretty amazing molecular machines.
You manipulate DNA to modify the types of proteins known as enzymes. What do these proteins do?
Enzymes catalyze all the reactions of life. They're what allow you to extract materials and energy from your environment and turn that into muscle and tissue and fat. That's all done by enzymes. They're pretty remarkable chemists — they're even better than Caltech chemists.
I wanted to make enzymes that would solve human problems, not just problems for a cell that makes them.
What kinds of problems did you have in mind?
I was interested in the industrial side: How do you use biology to make the chemicals and products we use in our daily lives? That has developed now to where it's a really vibrant industry.
Can you give me some examples?
You can make biofuels with enzymes. You can cure diseases with enzymes. You can clean your clothes better with enzymes.
The blockbuster diabetes drug Januvia made by Merck is manufactured now using an enzyme. In the past, it was manufactured using a chemical process that involved toxic metals and tons of organic solvent waste. They've replaced that completely.
How did you get the idea for directed evolution?
It came in almost a fit of desperation.
I was an assistant professor at Caltech, which has lofty aspirations for doing really important work, and I was pretty clueless. I didn't know how to make proteins. So I started doing lots of experiments simultaneously, and I realized that's exactly what nature does.
How long does it take for you to "evolve" a protein with the particular qualities you want?
Sometimes it's one generation; sometimes it's 31 generations. It really depends on where you start, how good is your starting point and how far you have to go — and that's entirely determined by the application.
Aren't you nervous about manipulating DNA?
We've been modifying the biological world at the level of DNA for thousands of years. We've made corn that can feed people, and we've made chickens that have big breasts and we've made cats with stripes.
Now with these new techniques of being able to actually go in to cut and paste DNA, we could do that in a very directed fashion.
You have four brothers and three sons. It sounds like you're surrounded by men at work and at home!
Yeah, it's true.
I've always made a conscious effort to have as diverse a group as possible. I love the fact that new ideas can come from anywhere. It's impossible to predict — and it's not always the smartest people on paper that come up with the best ideas.
This conversation has been edited for length and clarity.
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May 25, 8:57 a.m.: This article has been updated with new information throughout.