Born in 1905, the Spanish-born molecular biologist fled war in Europe to come to the United States in 1941.
For thirty-two years, beginning in 1942, he taught at New York University. One of his interests was RNA (ribonucleic acid), a compound found in living cells that is important in cell reproduction.
Ochoa isolated an enzyme that allowed him to perform the first test-tube synthesis of RNA. His discovery helped open the way for modern genetic engineering.
For his research, he became corecipient of the 1959 Nobel Prize in physiology or medicine.
In 1985, Ochoa returned to his native Spain, where he lived until his death in 1993.