1952
Alfred Hersy and Martha Chase proved that DNA was of a hereitary material. By using Bacteriophage, they used radioactive isotopes to label the bacteriophages. They took two seperate phage culters and treated one with radioactive sulfur (the protein capsule was in this culture) and the other with radioactive phosphorus (this one containing the DNA core.)
Looking at the results, Hershey concluded that most of the phage DNA remained in teh bacterial cells, most of the infected bacteria were capable of producing phage, and the phage protein removed from the cells consisted of more or less empty phage coats. These phage coats only served as transport of DNA from cell to cell and that they played no role in phage growth.
