LBS 333        Topics in the History of Genetics and Molecular Biology    Fall 2000
 
 



 

The Hershey-Chase Experiment




    Legend: Illustration of the 1952 experiment connecting DNA and heredity.

    Side by side experiments are performed with separate bacteriophage (virus) cultures in which either the protein capsule is labeled with radioactive sulfur or the DNA core is labeled with radioactive phosphorus.

        1.The radioactively labeled phages are allowed to infect bacteria.

        2.Agitation in a blender dislodges phage particles from bacterial cells.

        3.Centrifugation concentrates cells, separating them from the phage particles left in the supernatant.
 

    Results:

        1.Radioactive sulfur is found predominantly in the supernatant.

        2.Radioactive phosphorus is found predominantly in the cell fraction, from which a new generation of infective phage can be isolated.

    Conclusion: The active component of the bacteriophage that transmits the infective characteristic is the DNA. There is a clear correlation between DNA and genetic information.
 





 


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