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TEACHING BIOTECHNOLOGY. Philosophy: In conveying the incredible power and potential of biotechnology to students, it should always be balanced with discussion of the Ethical, Legal, Social/cultural Issues (E.L.S.I.) associated with this technology.
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TEACHING BIOTECHNOLOGY Philosophy: In conveying the incredible power and potential of biotechnology to students, it should always be balanced with discussion of the Ethical, Legal, Social/cultural Issues (E.L.S.I.) associated with this technology.
Considering our past experience with new innovative technologies, we must consider the long term detrimental consequences as well as short term solutions to problems. LBNL ELSI Home Page http://www.ornl.gov/sci/techresources/Human_Genome/elsi/elsi.shtml
As long as we keep this perspective, biotechnology has the potential to address many problems: • Energy/Climate change • Depletion of resources • Pollution • Disease/Health care • Food production
How can biotechnology address these problems? • It requires a new paradigm in thinking about technological solutions: • Rather than learning about nature in order to tame or overcome it, learn to mimic the way nature does it!
BIOMIMICRY • Energy production: mimic photosynthesis to create voltage potentials, splitting H2O into H2 and O2 • New materials that are biodegradable, no toxic wastes • Air and water purification • Food production?? http://www.ls9.com/
A brief history of the scientific discoveries leading to recombinant DNA technology • 1953 Watson & Crick discover the structure of DNA
How can scientists begin learning about the structure and function of this HUGE molecule (Genomic DNA)?
How can scientists begin learning about the structure and function of this HUGE molecule (Genomic DNA)? • Need a way to break it down into bite-size pieces • Need a way to amplify the bite-sized pieces so there is enough to manipulate and study.
In 1963 an enzyme was discovered in bacteria that cuts double stranded DNA at a specific nucleotide sequence • Restriction Enzyme “molecular scissors” Xba I T▼CTAG AA GATC▲T A▼AGCT TT TCGA▲A HindIII http://www.dnai.org/index.htm
Shortly after restriction enzymes were discovered, Kornberg discovered DNA Ligase during his investigation of DNA replication. • DNA Ligase forms phosphodiester bonds in the sugar-phosphate backbone between DNA fragments http://www.dnai.org/index.htm
Plasmids can be extracted out of bacteria, manipulated, and introduced back into bacteria. Replicate independently from genome to high copy number.
Selection of recombinant plasmids by inactivation of b-galactosidase gene expression
PLASMID MINI-PREPARATION • Procedure: • Concentrate cells: Spin down, resuspend in GTE. • Break cells open, denature DNA and proteins: Add SDS/NaOH • Neutralize NaOH, precipitate genomic DNA and protein: Add Potassium Acetate/Acetic acid • Remove protein/DNA “snot”: Centrifuge, keep supernatent (liquid portion) containing plasmid and RNA. • Concentrate nucleic acid: Isopropanol precipitation, ethanol wash. • Dry nucleic acid pellet