George W. Beadle

George W. Beadle, 1958

George Wells Beadle (October 22, 1903 – June 9, 1989) was an American scientist in the field of genetics, and Nobel Prize in Physiology or Medicine Nobel laureate who with Edward Lawrie Tatum discovered the role of genes in regulating biochemical events within cells.

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 led them to propose a direct link between genes and enzymatic reactions, known as the “one gene, one enzyme” hypothesis.