jan 1, 1952 - Alfred Hershey and Martha Chase: Protein is not Hereditary Material
Description:
Hershey's and Chases experiments involved a virus that infects the E. Coli bacterium. The T2 bacteriophage they used to inject the E. Coli was known to consist of proteins and DNA, but the roles they played in the growth of the bacteriophage was unclear.
To determine the roles they play in infection, they took advantage of their chemical differences. Proteins contain sulfur (DNA does not), and DNA contains phosphate (proteins do not.)
Through a series of complicated steps in their experiment, they discovered that "Protein probably has no function on phage growth. DNA has some function, further chemical infrences should not be drawn from the experiments presented" (Hershey & Chase, 1952).
Although they did not conclude that DNA was the hereditary material, they point out that further experiements needed to be done in order to establish the role that DNA played in bacteriophage replication.
Source:
https://paulingblog.wordpress.com/2009/08/18/the-hershey-chase-blender-experiments/
https://www.khanacademy.org/science/biology/dna-as-the-genetic-material/dna-discovery-and-structure/a/classic-experiments-dna-as-the-genetic-material
Added to timeline:
DNA TIMELINE
Yana Kryvyak
Date:
Images:
![]()
