1911-1980

American biochemist who received the 1972 Nobel Prize for Chemistry, shared with Stanford Moore and Christian Anfinsen, for research on the complex structure of protein molecules. Stein helped develop an efficient way of analyzing and identifying the 20 common amino acids that make up protein molecules. Using a special technique, chromatography, Stein and Moore were able to determine the exact arrangement of all 124 amino acids in ribonuclease. Their technique became the basis for modern protein analysis, which has been instrumental for medical advances, genetic engineering, and criminal investigations.