History
Griffith Experiments
British Doctor
vaccine for pneumonia
used rough and smooth strains of bacteria
smooth
virulent
rough
temperate
trials
live r strains
mice live
live s strains
mice die
heat killed s
live
heat killed r
live
heat killed s and live r
die
Avery, MacLeod, McCarthy
duplicated Griffiths experiment
added a step
live S + live R + DNAase
enzyme that destroys DNA
mice lived
DNA was the transforming factor
Chargoff
American
discovered base pair rule b/c amount of
A=T
C=G
Alfred Hershey and Martha chase
~1950
used E.coli bacteria and bacteriophage
virus that kills bacteria
DNA contains phosphorus but not sulfur
proteins can contain sulfur but not phosphorus
when phosphorus or sulfur are radioactive, the result is
hot DNA or
hot protein
used radioactive isotopes to tag DNA and proteins
"proved" that DNA was the hereditary material
James Watson and Francis Crick
won Nobel prize in 1962 for discovering the structure of DNA
simply put together the pieces other scientists had discovered about the molecule
James Watson
22 year old American genius
immature
no people skills
(Mrs. Miller met him)
Francis Crick
Oxford researcher
assigned the task of "baby-sitting" the american genius
found girlfriends for Watson
33
Roslyn Franklyn
took pictures of DNA and found there were two types
right turning
perfect double helix
left turning
complicated/messy
believed it was the left turning one
Watson noticed a picture of right turning DNA in her office
figured out what DNA looked like
told Crick about it and they built a paper model
Roslyn Franklin went to the University of Italy
Watson and Crick started on the metal model
Francis Crick went on to psychology
James Watson wrote many books on physiology
They also figured out how DNA replicates
Cold Springs Harbour Laboratory
Center of U.s. DNA and molecular genetics research
located on Long Island, New York
Labs are named after people like Avery, McCarthy etc.
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