Download Recombinant DNA Technology

Recombinant DNA Technology
I. Applications of DNA Technology:
A. Recombinant DNA: involves analyzing and manipulating specific DNA
fragments (genes)
B. DNA Cloning: involves making multiple copies of a DNA fragment.
Examples:
1. Tobacco plant glows in the dark using firefly DNA
2. Engineering fruits (oranges, apples, tomatos, etc.) to be resistant to
insects and others nuisance
3. Engineering fruits to grow bigger and stay ripe longer
4. Engineering antibiotics against bacterial and viral infections
5. Cancer suppressor gene--p54 gene, etc.
6. Genetically engineering vegetables (spinach, etc.) to be more
nutritious
7. Cloning healthy cows to provide enough food for the entire world
8. Improving appearance—baldness, facial hair, etc.
9. Genetically engineering “life”---invitro fertilization
II.
Basic ingredients needed for DNA Recombination:
A. Know the gene of interest and the species carrying that gene
B. Need a species that can rapidly replicate its DNA and divide
C. Need a species containing many restriction sites on its DNA
D. Need restriction enzymes—these enzymes are able to cut double stranded
DNA molecules at a specific nucleotide pair sequence
E. (Optional) Need Linkers—Linkers are a single strand of nucleic acid use in
promoting DNA cloning
F. Enzymes and technology: DNA ligase, DNA polymerase, PCR, etc.
III.
Bacteria (E. coli, etc.) are the most favorable species in DNA Recombination and
DNA Cloning
A. Each bacteria has a single chromosome, a circular DNA molecule
B. Many bacteria also have plasmids---a small circular molecule of DNA
containing only a few genes—containing lots of useful and common
restriction enzymes
IV.
Basic process of DNA Recombination using bacteria:
A. Isolate the gene of interest (penicillin—an antibiotic) from the bacteria #1 by
adding probes and then restriction enzymes
1. Probes--are short DNA sequences that are assembled from
radioactively labeled nucleotides
B. Modify the gene of interest by adding Linkers (if required) after isolating the
gene
C. Insert the radioactively labeled gene back into a host bacteria #2
1. Incubate the bacteria for 48-72 hours at 37 degrees (depending on the
bacteria)
D. Test the bacteria to determine if DNA recombination was successful by
expose the bacteria to radioactive (filters) Or Culturing bacteria on enzymes or
antibodies