U.S. #4544

2011 44¢ Severo Ochoa

American Scientists

Issue Date: June 16, 2011

City: St. Paul, MN

Quantity: 30,000,000

Printed By:  Banknote Corporation of America, Sennett Security Products

Printing Method: Offset

Color: multicolored

As Severo Ochoa (1905-93) accepted his Nobel Prize in 1959, he told the crowd, “These particles are at the threshold of life and appear to hold the clue to a better understanding of some of its most fundamental principles.”  Ochoa won the Nobel Prize in Medicine for his work with ribonucleic acid (RNA).  

Three years earlier, Ochoa had discovered how to artificially create proteins (the main building blocks of life).  He isolated an enzyme naturally designed to destroy RNA, and reversed the process to create it instead.  It was the first time molecules were combined outside a living organism. 

Along with DNA, RNA is responsible for controlling cellular function and heredity.  Ochoa speculated at the time that being able to combine RNA in the laboratory might lead to the creation of genetic material in a test tube – to grow living matter.

Ochoa came to the United States in 1941, after beginning his career in his home country of Spain.  Ochoa had left Spain with his wife, Carmen, during the Spanish Civil War in the 1930s.  He studied and taught in Scotland, Germany, and Great Britain, and became a U.S. citizen in 1956.  But fifty years after leaving, the couple returned to Madrid to join a newly created facility named in his honor – the Severo Ochoa Center for Molecular Biology.