Video 34: Douglas Hanahan, clip 1
Doug Hanahan is a professor of biochemistry at UCSF. He refined transformation techniques, and developed the current theories on the mechanisms of DNA uptake.
douglas hanahan, dna transformation, dna uptake, transformation techniques, mandel, biochemistry mechanisms
- ID: 16715
- Source: DNALC.DNAFTB
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Size of DNA and transformation efficiencies.
The problem of getting DNA into a bacteria.
How big are those bacterial pores?
Definitions of "cloning."
Doug Hanahan refined transformation methods for DNA uptake into bacteria.
DNA transformation is a naturally occuring but rare event in which DNA can be transferred into bacteria. In 1970, Morton Mandel and Akiko Higa discovered a way to make E. coli more "competent" for transforming foreign DNA. Their calcium chloride method is
Stanley Cohen and Herbert Boyer inserted the recombinant DNA molecule they created into E. coli bacteria by means of a plasmid, thereby inducing the uptake and expression of a foreign DNA sequence known as "transformation."
Stanley Cohen and Herbert Boyer transform bacteria with a recombinant plasmid, and Doug Hanahan studies induced transformation.
Stanley Cohen speaks about his and Herbert Boyer's experiment to make the first plasmid that had been engineered to contain foreign DNA.
Experiment with rough and smooth Pneumococcus DNA.