Edward Lawrie Tatum

Edward Lawrie Tatum (December 14, 1909 – November 5, 1975) was an American geneticist. He shared half of the Nobel Prize in Physiology or Medicine in 1958 with George Wells Beadle for showing that genes control individual steps in metabolism. The other half of that year's award went to Joshua Lederberg. Beadle and Tatum's key experiments involved exposing the bread mold Neurospora crassa to x-rays, causing mutations. In a series of experiments, they showed that these mutations caused changes in specific enzymes involved in metabolic pathways. These experiments, published in 1941, led them to propose a direct link between genes and enzymatic reactions, known as the "one gene, one enzyme" hypothesis. Tatum went on to study genetics in...