The University of Notre Dame Carrier Medalist for 2026, will share her lecture, 鈥淚nnovation by Evolution,鈥� on Monday, Sept. 14 in Jordan Hall of Science.
One of the recipients of the , Arnold is the Linus Pauling Professor of Chemical Engineering, Bioengineering, and Biochemistry at the California Institute of Technology. She won the Nobel Prize for pioneering "directed evolution" to engineer new enzymes, which are proteins that speed up chemical processes. Her work has helped develop 鈥済reen鈥� pharmaceutical manufacturing and has made renewable fuels possible.
Arnold鈥檚 talk for , presented in honor of Mary Burke Ryan, will share recent studies from her laboratory that show how directed evolution of enzymes can teach biology to carry out entirely new chemistry.
鈥淏iology can learn to do chemistry invented by human beings much more efficiently and without the toxic components humans use,鈥� she said. 鈥淎nd even more exciting, biology can learn to do chemistry that humans dream of but cannot yet do.
鈥淭hese include transformations used to make important products we need in our daily lives.鈥�
A precocious child who grew up with four brothers, Arnold knew she was as good at math, if not better, than they were. She graduated magna cum laude from Princeton University with a degree in mechanical and aerospace engineering, though she took a wide variety of classes in different areas before settling into her major.
After a job at the former Solar Energy Research Institute in Colorado (now the National Laboratory of the Rockies), and plenty of world travel, Arnold completed her doctoral degree in chemical engineering at the University of California, Berkeley. She credits having four brothers with cementing her lack of fear of working with men, which is something she needed in the 1970s and early 1980s when completing her degree and landing that first engineering job.
Even in 2026, many women shy away from engineering and some areas of science.
鈥淲omen often choose not to do it,鈥� she said. 鈥淭o change what they choose, you have to make it interesting; you have to make it impactful for people and planet. It has to compete with the many other things women find interesting.
鈥淏ecause when they do it, they succeed very well.鈥�
Throughout her career, Arnold has turned her attention toward specific applications of her work that are best done by industry, several times encouraging students and postdoctoral fellows to start companies. Today half of her research group is working with artificial intelligence, and she and her students were pioneers in the use of machine learning for engineering proteins.
Prizes like the Carrier Medal allow young people to see what it might be like to be a scientist or engineer, and could move them to consider a future STEM career, Arnold said.
鈥淭he Nobel Prizes, for example, inspire young people in the farthest reaches of the world," she said. 鈥淚 get letters from students in sub-Saharan Africa, Egypt, Indonesia, South America who say that it鈥檚 exciting and inspiring to see a woman win a Nobel Prize.
鈥淔or example, non-scientists might not realize their cell phones, or even their laundry detergents, are full of clever inventions, and awarding prizes reminds them that these were thought up by humans.
鈥淎wards sometimes reach even more people than a science classroom,鈥� she said.
The Carrier Medal is awarded annually in recognition of sustained, outstanding achievements in the sciences. It celebrates those whose pioneering contributions have advanced the frontiers of scientific knowledge and promoted the betterment of humanity.
Originally published by at on August 03, 2026.