The Nobel Prize in Physiology or Medicine 1958
Born: 23 May 1925, Montclair, NJ, USA
Died: 2 February 2008, New York, NY, USA
Affiliation at the time of the award: University of Wisconsin, Madison, WI, USA
Prize motivation: "for his discoveries concerning genetic recombination and the organization of the genetic material of bacteria."
Prize share: 1/2
It was long thought that bacteria multiply by dividing, so that all bacteria have the same genetic make-up. Joshua Lederberg and Edward Tatum demonstrated in 1946 that bacteria's genes can also change in a way similar to that of sexual reproduction seen in more complex organisms. Bacteria can go through a phase in which two bacteria exchange genetic material with one another by passing pieces of DNA across a bridge-like connection. Joshua Lederberg also proved the phenomenon known as transduction, in which DNA is transferred between bacteria via bacteriophages.
Their work and discoveries range from how cells adapt to changes in levels of oxygen to our ability to fight global poverty.
See them all presented here.