December 4th
An American biologist who won the Nobel Prize in Physiology or Medicine in 1969, along with Max Delbrück and Salvador Luria. This award was given to the study of bacteriophage (a virus that infects bacteria). This was the famous “Mixer Experiment” (1956). Hershey used isotope-labeled phage to infect bacterial colonies and inject their genetic material into host cells. He then stirred them in a waring blender and tore the bacteriophage particles from the bacterial wall without tearing the bacteria. While investigating the bacteria, Hershey discovered that only phage DNA was inserted into them and there were no detectable proteins. This showed that DNA was sufficient to transfer all the genetic information to the bacteria needed to produce more phage.
Born 4 Dec 1908; died 22 May 1997 at age 88.