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Creating Recombinant DNA. AP Biology Biotechnology Unit Seefloth. Biotechnology. Uses living organisms Improves society EX: Medicine, antibody production for cancer treatments, engineered food Not a “new thing” Use of micro-organisms is 10,000 years old
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Creating Recombinant DNA AP Biology Biotechnology Unit Seefloth
Biotechnology • Uses living organisms • Improves society • EX: Medicine, antibody production for cancer treatments, engineered food • Not a “new thing” • Use of micro-organisms is 10,000 years old • Bread (yeast), cheese (bacteria), beer (yeast)
biotechnology Yeast in bread Bacteria curdles cheese Glow Fish with Jelly Fish Gene GFP gene
Recombinant DNA Technology • Produces large amounts of substances • Transfers a foreign gene into a host organism (bacteria is preferred) • Host reproduces, passing on the gene in large #s • Many foreign genes = a lot of new protein exists • EX: E.colibacteria contains human insulin gene and large amount of insulin can be harvested for diabetic patients
Where to begin? • Step One: identify the gene of interest– what protein do they need manufactured? • Look at the protein and identify the amino sequence of that protein • Locate the complimentary sequence on the mRA • Backtrack to DNA and find the original sequence
Step 2: Use restriction enzyme(s) to cleave the desired gene from the DNA • Need a “sticky end” cut to ensure this gene can be fused into the host organism’s DNA
We need a way to transfer the gene into the host, so…. • Step 3: Locate a plasmid • Use a gene “taxi” from bacteria called a PLASMID (circular DNA). • Create sticky ends on either side of the plasmid so it can fuse with the gene of interest • Plasmids have a replication origin that copies the same plasmid again and again
Step 4: Fuse the plasmid and the gene together • Utilizes the enzyme, Ligase (glue)= phosphodiester linkages • Complimentary base pairs are joined together
Step 5: Mix the plasmids with the host bacteria and test to see if successful • How to know if this worked? • Need a visual cue– antibiotic resistance (clearly grows on a medium that would normally kill them) • Glows green? The GFP (green fluorescent protein) is a visual marker • Test plasmid