The Hershey-Chase
experiment was a
landmark experiment done in 1952 which showed that
DNA is the
hereditary material in
cells. The
scientists who conducted the experiment, Martha Hershey and Alfred Chase, wanted to know if it was the
viral DNA or the
protein coat that was the
genetic code material which could incorporate into the cellular machinery of
E. coli bacteria. So, their experiment involved allowing a
bacteriophage virus which contained
DNA labeled with
32P (an
isotope of
phosphorus) and a
protein labeled with
35S (an
isotope of
sulfur) to attach to some
E. coli. When the
bacteriophages were later removed, they found that it was the
32P (and thus the
DNA) that had entered the
bacterial
cells rather than the
35S (which would have indicated the
protein).
Today, the Hershey-Chase experiment is reproduced by biochemistry students around the world as part of their education.
From the science dictionary at http://biotech.icmb.utexas.edu/