The genetic information of an organism is stored in DNA molecules which, via RNA molecules, are converted during the formation of proteins. The chemical processes inside cells are controlled by a type of protein called enzymes. William Stein and Stanford Moore studied the enzyme ribonuclease, which divides RNA into smaller components. In the late 1950s, the pair succeeded in providing a detailed understanding of the enzyme's active center and in elucidating the connection between the structure of the molecule and its ability to speed up biochemical reactions.