But now that she has become the first woman ever to win the prestigious Millennium Technology Prize — it was awarded in Helsinki, Finland, on May 24 — Arnold is truly one of a kind.
And she knows that in addition to a big cash award (1 million euros, or about $1.3 million), the prize brings an opportunity to spotlight the gender gap in STEM (science, technology, engineering and math) careers and to be a role model for other women.
"I hope that my getting this prize will highlight the fact that yes, women can do this, they can do it well, and that they can make a contribution to the world and be recognized for it," Arnold told The Huffington Post in an email. "I hope that women will see that one can have a rewarding career in science and technology."
Arnold, 59, won the prize for "her discoveries that launched a field known as directed evolution," according to a statement issued by Technology Academy Finland, the organization that awards the prize. To learn more about the field, and about Arnold herself, HuffPost Science posed a series of questions to her via email. Here, lightly edited, are her answers:
Did you always want to be a scientist?
I did not choose to become a researcher until I was almost 30. I tried other careers, but science spoke to me more and more, especially after I started studying the biological world and all the amazing molecular machines made by nature.
As a little girl, I thought I might be a heart surgeon, CEO of a multinational company or even a diplomat some day (until I figured out I had no diplomatic skills). When I went to college, I never really thought about being a scientist or an engineer, but of course that was always on the list of possibilities.
I had tried lots of odd jobs — from taxi driver to waitress to assembling electronic devices — and later a few science and technology jobs in nuclear power and solar energy. But I loved languages, I enjoyed economics, I spent every break traveling and seeing different cultures. I loved learning and did not think too much about the future until one day it happened!
Why do women continue to be underrepresented in engineering and other STEM fields?
Because talented women choose to do other things. But if they knew how important technology is for supporting our well-being and that of the planet, and how fun it can be, more would choose STEM fields.
What barriers keep women from choosing STEM careers?
I believe that some women still face external barriers, but other barriers are more self-imposed: lack of confidence or desire to compete and a misunderstanding of what science and technology can contribute to society.
Science is not for everyone; it takes a lot of time and devotion to become really good, and the same is true for engineering. You have to love it. What I see is that the most talented women have many opportunities. Whether they choose to pursue science or engineering depends on how they feel about their whole life experience, perhaps more so than men. Opportunities today are excellent, but there are challenges to having a family and competing at the highest levels that women often feel more acutely.
What can be done to eliminate these barriers?
At the very least, girls should not be discouraged from using their natural talents in mathematics and science. Even better, they should be encouraged and praised.
What's a typical workday like for you?
Rich, never boring, something new and interesting every day. Full of brilliant young people who want to change the world.
So now about your research -- what is directed evolution?
It's a technology that allows us to reliably create improved proteins for a wide range of applications. Just as farmers and breeders have used artificial selection processes over thousands of years to create higher-yielding crops or pets that please us, we can direct the evolution of proteins to perform better in applications, from laundry detergents to green chemistry.
Modern methods of DNA manipulation allow us to make iterations of mutations and artificial selection on a gene rather than in an organism, and to shorten the generation time to a few days. That way we can accumulate beneficial mutations in the gene that encodes the protein, making it better and better until it meets our needs.
What makes proteins so important?
Proteins are the workhorses of life, responsible for nearly all the interesting things we and other organisms can do. Just one (very important) class of proteins, the enzymes are responsible for turning food (for example, for some microbes this means sunlight, carbon dioxide, sugar, etc.) into all the materials and energy needed to support life and reproduce life. That’s pretty amazing chemistry, and we should learn how to harness that for our own purposes.
We have already been using microbes and the enzymes in them to improve our lives for thousands of years, from making bread, beer, wine, cheese -- to, more recently, having laundry detergents that take stains off of clothes in cold water (thus saving significant energy), making fuels and chemicals from renewable resources or making drugs to treat diabetes.
How does directed evolution differ from evolution as we commonly think of it?
It differs from natural evolution in that it is directed by the researcher. Mutations are directed (by me) to a specific gene, and since the researcher has a goal in mind, it is also directed in that sense.
How is directed evolution being used commercially?
Directed evolution has had big impact in the fields of drug synthesis. Many popular drugs, including the cholesterol-lowering drugs simvastatin and atorvastatin, have been developed with the help of directed evolution. The same is true for making consumer products (key ingredients for creams, laundry detergents, animal and human nutrition products and many more) and for making non-ethanol fuels like isobutanol from renewable plant resources.
What are the biggest advances that have come from the commercial application of directed evolution?
My former student and one of the first people to use directed evolution, Dr. Jeffrey Moore, and his collaborators figured out how to manufacture the diabetes drug Januvia using an evolved enzyme. Their process replaces chemical methods that were far from optimal, lowering the cost of the drug and especially the waste products. Their process won many awards, including the President's Green Chemistry Challenge.
Many companies now incorporate enzyme catalysts into their processes. More will do so as we move to greater sustainability in manufacturing.
A number of companies that make fuels and chemicals from renewable resources have used DE to optimize enzymes. Enzymes optimized by directed evolution are being used to make nutritional products for humans and animals, fuel from biomass and to test new drugs for toxicity. They are being used directly to treat human disease.
Engineered enzymes are used in everything from DNA sequencing to glucose sensors for diabetes, laundry detergents and food processing.
What do you foresee for directed evolution in the future?
The wonderful thing about directed evolution is that it is both simple and general. Because the technology is accessible, it can be implemented in any laboratory. It opened up a new way for people to look at the inventions of the biological world and fit them into their own creations.
So many clever people all over the world have taken this technology and done all manner of brilliant things with it, things I would never have thought of. This will continue in the future.
What are you going to do with all that prize money?
I will use some of it to invest in work done at Provivi, a startup I cofounded with two of my former students, Peter Meinhold and Pedro Coelho. Provivi is developing the non-toxic alternatives to pesticides, which I think is such an important goal.
Why so important?
Pesticides get into our food, streams and rivers and cause all manner of harm. Imagine spraying a little bit of "perfume" in a field to confuse the insect pests so that they can't mate. If they can't mate they are not going to damage your crops. Wouldn't it be wonderful to do that instead of dumping highly toxic pesticides? Our hope is to make these complicated insect perfumes quite cheaply using enzymes.
Is there a particular scientific question you're trying to answer?
I am very interested in the evolution of novelty — how do new functions appear in the biological world. I am tackling this question by evolving enzyme catalysts that catalyze chemical reactions not known in the biological world.