George Beadle

In 1958 he shared one-half of the Nobel Prize in Physiology or Medicine with Edward Tatum for their discovery of the role of genes in regulating biochemical events within cells.

[5] 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.

He was the son of Chauncey Elmer Beadle and Hattie Albro, who owned and operated a 40-acre (160,000 m2) farm nearby.

[citation needed] In 1935 Beadle visited Paris for six months to work with Professor Boris Ephrussi at the Institut de Biologie physico-chimique.

Together they began the study of the development of eye pigment in Drosophila which later led to the work on the biochemistry of the genetics of the fungus Neurospora for which Beadle and Edward Lawrie Tatum were together awarded the 1958 Nobel Prize for Physiology or Medicine.

In 1936 Beadle left the California Institute of Technology to become Assistant Professor of Genetics at Harvard University.

Further evidence obtained soon after the initial findings tended to show that generally only a single step in the pathway is blocked.

This led directly to the one gene-one enzyme hypothesis, which, with certain qualifications and refinements, has remained essentially valid to the present day.

At the time of the experiments (1941), non-geneticists still generally believed that genes governed only trivial biological traits, such as eye color, and bristle arrangement in fruit flies, while basic biochemistry was determined in the cytoplasm by unknown processes.

[citation needed] Beadle died on June 9, 1989 at a retirement community in Pomona, California from complications of Alzheimer's disease, aged 85.