The Hershey–Chase experiments were a series of experiments conducted in
1952 by Alfred Hershey and Martha Chase that helped to confirm that DNA is the
genetic material. While DNA had been known to biologists since 1869, many
scientists still assumed at the time that proteins carried the information for
inheritance because DNA appeared simpler than proteins. In their experiments,
Hershey and Chase showed that when bacteriophages, which are composed of DNA
and protein, infect bacteria, their DNA enters the host bacterial cell, but
most of their protein does not.
Hershey and Chase concluded that protein was likely not to be the hereditary genetic material. However, they did not make any conclusions regarding the specific function of DNA as hereditary material, and only said that it must have some undefined role.
Confirmation and clarity came a year later in 1953, when James D. Watson and Francis Crick correctly hypothesized, in their journal article "Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid", the double helix structure of DNA, and suggested the copying mechanism by which DNA functions as hereditary material. Furthermore, Watson and Crick suggested that DNA, the genetic material, is responsible for the synthesis of the thousands of proteins found in cells. They had made this proposal based on the structural similarity that exists between the two macromolecules, that is, both protein and DNA are linear sequences of aminoacids and nucleotides respectively.
Hershey shared the 1969 Nobel Prize in Physiology or Medicine with Max Delbrück and Salvador Luria for their “discoveries concerning the genetic structure of viruses.
Hershey-Chase experiment:
http://highered.mheducation.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120076/bio21.swf::Hershey+and+Chase+Experiment
Paper:
http://jgp.rupress.org/content/36/1/39.full.pdf
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2147348/
Sources:
http://en.wikipedia.org/wiki/Hershey%E2%80%93Chase_experiment
http://www.rsc.org/chemistryworld/Issues/2003/April/story.asp
Reference:
http://www.nobelprize.org/nobel_prizes/medicine/laureates/1969/index.html
Hershey and Chase concluded that protein was likely not to be the hereditary genetic material. However, they did not make any conclusions regarding the specific function of DNA as hereditary material, and only said that it must have some undefined role.
Confirmation and clarity came a year later in 1953, when James D. Watson and Francis Crick correctly hypothesized, in their journal article "Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid", the double helix structure of DNA, and suggested the copying mechanism by which DNA functions as hereditary material. Furthermore, Watson and Crick suggested that DNA, the genetic material, is responsible for the synthesis of the thousands of proteins found in cells. They had made this proposal based on the structural similarity that exists between the two macromolecules, that is, both protein and DNA are linear sequences of aminoacids and nucleotides respectively.
Hershey shared the 1969 Nobel Prize in Physiology or Medicine with Max Delbrück and Salvador Luria for their “discoveries concerning the genetic structure of viruses.
Hershey-Chase experiment:
http://highered.mheducation.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120076/bio21.swf::Hershey+and+Chase+Experiment
Paper:
http://jgp.rupress.org/content/36/1/39.full.pdf
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2147348/
Sources:
http://en.wikipedia.org/wiki/Hershey%E2%80%93Chase_experiment
http://www.rsc.org/chemistryworld/Issues/2003/April/story.asp
Reference:
http://www.nobelprize.org/nobel_prizes/medicine/laureates/1969/index.html
corina marinescu
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