George Beadle and Edward Tatum jointly publish a paper on their experiments using the fungus Neurospora crassa to establish that particular genes are expressed through the action of correspondingly specific enzymes. The first gene to be identified controlled the synthesis of an enzyme in a series that led to generation of niacin. This report is the genesis of the “one gene-one enzyme” concept. With Lederberg, Beadle and Tatum are awarded the Nobel Prize in Medicine or Physiology in 1958.
Beadle, G. and E. Tatum. 1941. Genetic control of biochemical reactions in Neurospora. Proc. Nat. Acad. Sci. 27: 499-506. In Microbiology: A Centenary Perspective, edited by Wolfgang K. Joklik, ASM Press. 1999, p.308 [pdf]