jan 1, 1952 - Alfred Hershey & Martha Chase
Hershey and Chase studied a bacteriophage known as T2. They knew that T2 would attach to a host cell and dispense the instructions to generate the virus into the host cell; however, they thought that this genetic material was a protein. They used a radioactive isotope of sulfur to radio label the proteins and a radioactive isotope of phosphorus to radio label the phosphorus in DNA. In the experiment, they allowed T2 to attack the bacteria, then placed each culture in a blender in order to get rid of any remaining bacteriophages. After that, they centrifigured the cultures in order to separate the bacteria from the T2. They then used the radioactive sulfur and phosphorus and found that the bacteria contained mainly phosphorus and T2 contained mainly sulfur. At the end of this experiment, Hershey and Chase concluded that DNA was injected into the host cell, not protein.
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