Medical Interventions 4.1.2 Protein Factories

Define plasmid

A plasmid is a small loop/ring of circular DNA

What are 3 reasons why plasmids and bacterial cells are a helpful tool in genetic engineering?

1) one could add genes to a plasmid without ruining the rest of the genome.

2) plasmids can be cut and have extra DNA sequences added to it, with no damage and can connect back together after.

3) bacterial cells will reproduce what the plasmid is carrying making more of that gene.

What are the steps of using recombinant DNA techniques and plasmids to produce human insulin?

1) scientists build the human insulin gene in the laboratory.

2) they then remove a loop of bacterial DNA known as the plasmid

3) they then insert the human insulin gene into the plasmid

4) researchers return the plasmid to the bacteria

5) they put the recombinant bacteria in large fermentation tanks

6) in the tanks, the bacteria begin producing human insulin

7) scientists harvest the insulin made by the bacteria

8) the insulin is then purified for use.

What is GFP used for?

A visual marker

What is transformation?

The uptake of foreign DNA, often a circular plasmid.

What is a plasmid?

circular piece of autonomously replicating DNA who was originally evolved by bacteria, and can express the antibiotic resistant gene or can be modified to express proteins of interest.

What are some methods of transformation?

Electroporation, electric shock ( makes cell membranes permeable to DNA), and calcium chloride/heat shock.

What is the formula for transformation efficiency?

# of cells growing on a plate/amount of DNA on a plate

What are three useful applications of GFP in cellular biology and medical science?

Research of diseases, tracking progress of medicines, and for research

How are restriction enzymes and ligaments utilized in recombinant DNA technology?

Restriction enzymes cut the DNA strand and ligase glues it back together.

Why is it necessary to use the same restriction enzyme to cut the desired gene from the source and the plasmid?

Because restriction enzymes are very specific to what and where they are cutting.

What advantage would there be for an organism to be able to turn on and off a certain gene in response to certain situations?

The advantage would be survival. For example, angler fish are able to turn on and off the glowing 'light' to attract prey.

Bacterial cells produce many more proteins than just GFP. How can we separate the GFP from the other proteins?

We can separate GFP from other proteins by illuminating it with a UV light.