Two Israeli-American researchers received the Nobel Prize in Chemistry on Tuesday in Stockholm, Sweden.Israeli-born Prof. Arieh Warshel, who now lives in California, and South African-born Prof. Michael Levitt, who settled in Israel and also lives in the US, shared the $1.25 million with Austrian-born Prof. Martin Karplus, who fled to the US before the Holocaust.While not an Israeli, Karplus has a daughter who lives in Jerusalem and is a family physician.The three scientists received praise from the Nobel Prize selection committee for their “development of multiscale models for complex chemical systems.”Nine other laureates received Nobels at the Oslo ceremony as well.Science, Technology and Space Minister Yaakov Peri congratulated the two Israeli winners, saying it was unprecedented that a small country like Israel had eight Nobel Prize winners in the sciences.But at the same time, he continued, their success stressed the need to bring home leading Israeli scientists who had left the country because they could not find a proper place and budgets to continue their work here.Israel’s new generation of scientists will “continue to strive to reach the highest level that is epitomized by these two winners,” he said. “Science is one of the vital engines for economic growth. I will continue to push for investment of additional budgets for infrastructures, grants, research and development.”Warshel was born on Kibbutz Sde Nahum. Following his military service, he studied at the Technion-Israel Institute of Technology in Haifa, and then Rehovot’s Weizmann Institute of Science.“After that, we began to build unique models to better understand biological systems,” he said soon after learning that he had been chosen for the prize.“The discovery itself was in 1975, but it took many years to prove.”Levitt, a British, Israeli and American citizen, lauded Israel’s tradition of winning Nobel prizes.“Israel has traditionally had a very strong focus on education,” Levitt said when he heard about his win a few months ago.“This is wonderful,” he continued.“I think it’s important to continue that tradition, and I imagine it will.”The Weizmann Institute, where Levitt is a visiting professor and from which Warshel graduated decades ago, earlier congratulated the two for their achievement.Working with the late Prof. Shneior Lifson in Weizmann’s chemical physics department, Levitt and Warshel “developed a computer program that ran on the institute’s Golem computer – a powerful device in those days – to model molecules.This program had special relevance for large biological molecules,” the institute said in a statement.After completing his doctorate, Warshel went to work with Karplus at Harvard University, where they modeled retinal, the visual pigment, succeeding for the first time in combining classical modeling of the molecule with the quantum physics that could give them a glimpse into how it works.Warshel and Levitt reunited at the Weizmann Institute in 1972. According to the Nobel website, “Levitt and Warshel aimed high.” They developed a computer program that was “revolutionary because it could be used for any kind of molecule.” They also found a way to make the program more efficient, by focusing on the more interesting parts of the molecule.They went on to make seminal contributions to the field of computational biology by performing simulations to study how proteins work.Levitt was born in 1947 in Pretoria, South Africa. He received his PhD in 1971 from the University of Cambridge and was a member of the Weizmann faculty in the late 1970s and early 1980s. Today, he is a professor in cancer research at the Stanford University School of Medicine in California.Karplus, born in 1930, has a BA from Harvard University and a PhD from the California Institute of Technology. He is the Theodore William Richards emeritus professor of chemistry at Harvard University.