Navigation Links
Hershey-Chase experiment


The Hershey-Chase experiment was a series of experiments conducted in 1952 by Alfred Hershey and Martha Chase that identified DNA to be the genetic material of phages and, ultimately, of all organisms. A phage is a small virus that infects bacteria. It consists of a protein coat that encloses the genetic material. When a phage infects a bacterium, it inserts its genetic material into the bacterium, while its coat remains outside.


In a first experiment, T2 phages with radioactive 32P-labeled DNA infected bacteria. In a second experiment, T2 phages with radioactive 35S-labeled protein infected bacteria. In both experiments, bacteria were separated from the phage coats by blending followed by centrifugation. In the first experiment, most radioactivity was found in the infected bacteria, while in the second experiment most radioactivity was found in the phage coat. These experiments demonstrated that DNA is the genetic material of phage and that protein does not transmit genetic information.

Hershey shared the 1969 Nobel Prize in Physiology or Medicine for his discoveries concerning the genetic structure of viruses


More detailed description

Hershey and Chase knew that T2 consisted of only DNA and protein, and that they somehow manipulated host cells to produce new phages, but did not know if DNA or protein was responsible.

Hershey and Chase radioactively labeled E.Coli and T2 with 32P (phosphorus isotope) and 35S (sulfur isotope) because they knew DNA contains phosphorus, and protein contains sulfur, but not vice versa.

They infected the 32P E.Coli with 32P T2 and 35S E.Coli with 35S T2, and collected the progeny. The results found that the progeny collected from the 32P E.Coli and 32P T2 contained the 32P isotope, while the 35S strains did not, providing more evidence that DNA was the genetic information that bacteriophages inject into bacteria, not protein.


'"/>


(Date:4/17/2014)... of our ideas about domestication derive from Charles ... by British animal-breeding practices during the 19th century, ... improvement. , It is from Darwin that ... of captive animals from wild species and total ... But animal management in this industrial setting has ...
(Date:4/16/2014)... you cannot move your eyes up, and you cannot lift your ... so that your eyes look straight when they are rolled down ... to allow people a normal position of their head. In order ... happens. , In a paper published in the April 16 print ...
(Date:4/16/2014)... Biosciences Division of Lawrence Berkeley National Laboratory (Berkeley Lab) ... authority on the evolutionary design principles of cellular networks ... biology, has been named one of six recipients of ... Secretary Ernest Moniz. The E.O. Lawrence Award, the Department ...
Breaking Biology News(10 mins):The story of animal domestication retold 2The story of animal domestication retold 3The story of animal domestication retold 4Researchers track down cause of eye mobility disorder 2Berkeley Lab's Adam Arkin wins 2013 Lawrence Award 2Berkeley Lab's Adam Arkin wins 2013 Lawrence Award 3
... MCLEAN, Va., Nov. 29, 2012  Northrop Grumman Corporation (NYSE: ... proof of concept for an automated biometric information system ... will be operated for a trial period to enable ... enabled intelligence and to help determine the requirements for ...
... William Cooke, a professor in the UTSA College of Education ... selected to serve as the speaker of the Texas Chapter ... Tour. Over the course of a week, Cooke will deliver ... of ACSM,s Texas Chapter. "This is a big honor ...
... For the first time in its history, the American Society ... opening session of the ASCB,s Annual Meeting, for "An Evening ... Francisco, on Saturday, Dec. 15. Members of the ... will receive complimentary registration to the ASCB keynote addresses ...
Cached Biology News:Northrop Grumman Delivers Australian Automated Biometric Information System Trial Proof of Concept 2UTSA physiologist William Cooke named 2013 Lecture Series Speaker by Texas Sports Medicine Chapter 2Public invited to 'An Evening of Science & Art' at ASCB Annual Meeting 2
Other biology definitionOther Tags