Edward Tatum

Edward Tatum was an American biochemist and geneticist who, together with George Beadle, developed the one gene, one enzyme hypothesis through their experiments with X-ray-induced mutations in the bread mold Neurospora crassa in the early 1940s at Stanford University. Tatum brought particular biochemical expertise to the collaboration, helping to identify precisely which nutrient a mutant strain could no longer produce and to trace that defect to a specific missing enzymatic step, work that gave the abstract genetics of the time a concrete biochemical mechanism to point to. Tatum later collaborated with Joshua Lederberg on research into genetic recombination in bacteria, work that helped establish that bacteria, previously thought to reproduce only asexually, could exchange genetic material in a process resembling sexual reproduction. Tatum shared the 1958 Nobel Prize in Physiology or Medicine with Beadle and Lederberg for their discoveries concerning the genetic regulation of chemical processes within the cell.