The Royal Swedish Academy of Sciences awarded the prize of 8 million crowns ($1.25 million) to Karplus, Michael Levitt, and Arieh Warshel, noting that their work had transformed the modeling of chemical reactions, once done using plastic balls and sticks, and moved it into the computer age.
Born in Austria in 1930, Karplus was a child when his family fled the country's Nazi occupation, emigrating to the United States. He received a BA from Harvard University in 1950, and a PhD from Caltech in 1954, working with two-time Nobel Prize laureate Linus Pauling.
Karplus has made significant contributions to many fields in physical chemistry, including nuclear magnetic resonance spectroscopy, chemical dynamics, quantum chemistry, and, most notably, molecular dynamics simulations of biological macromolecules.
"The work of Karplus, Levitt, and Warshel is ground-breaking in that they managed to make Newton’s classical physics work side-by-side with the fundamentally different quantum physics," the Royal Swedish Academy said in its announcement. "Previously, chemists had to choose to use either or."
Complex chemical reactions, such as how a drug couples to its target protein, were generally understood at the molecular level. To learn what happens at the atomic scale, however, computers are needed to perform mathematically intense quantum theoretical simulations. Karplus, Levitt, and Warshel helped to bridge those models, offering researchers tools to gain a complete view of such interactions at all levels.
“This year's recipients have done important computational and mechanistic work on protein and enzyme catalysis,” said Rudolph Marcus, the Arthur Amos Noyes Professor of Chemistry at Caltech and the 1992 recipient of the Nobel Prize in Chemistry. “That Karplus was a student of Pauling brings the prize this year close to home.”
Karplus is the Theodore William Richards Professor of Chemistry, Emeritus, at Harvard University and director of the Biophysical Chemistry Laboratory, a joint laboratory of the French National Center for Scientific Research and the University of Strasbourg, France.