1. Lesson 2 – Recombinant DNA (Inquiry into Life pg. 500-507)
Cell Biology: DNA
Lesson 2 – Recombinant DNA (Inquiry into Life pg )

2. Describe Recombinant DNA, including:
Today’s Objectives
Describe Recombinant DNA, including:
Define recombinant DNA
Describe a minimum of 3 uses for recombinant DNA

3. Recombinant DNA Definition:
DNA having genes from 2 different organisms, often produced in the laboratory by introducing foreign genes into a bacterial plasmid
A vector is used to introduce recombinant DNA into a cell
A plasmid is the most common vector
They are small rings of DNA found in bacteria
The plasmid has to be removed from the bacteria and has to have a foreign gene inserted into it

4. Insertion of Foreign Genes
An enzyme (restriction enzyme) breaks the plasmid DNA ring
The new foreign DNA can now be attached to the plasmid
The enzyme ligase acts like glue which sticks the foreign DNA to the plasmid and recreates the ring

5. Insertion of Foreign Genes

6. Recombinant DNA The plasmid DNA is then put back into the bacteria
This bacteria will now replicate every cell the same as the one just put in
Eventually there are many copies of the foreign gene

7. Applications of Recombinant DNA
Recombinant human insulin
Human insulin gene inserted into bacteria E. Coli, used to treat diabetes
Recombinant human growth hormone (HGH)
Treats patients with pituitary gland deficiencies to support normal growth and development
Inserted into livestock to produce larger specimens
Recombinant blood clotting factor VIII
Blood clotting protein administered to patients with bleeding disorders
Recombinant hepatitis B vaccine
Control of hepatitis B virus
Diagnosis of HIV infection
Methods for diagnosing HIV have been developed using recombinant DNA
Herbicide and Insect resistant crops
Used in agriculture to reproduce genes that help crops resist attack by insects and protect crops from herbicides

8. Applications of Recombinant DNA
Generate DNA libraries which will catalogue all the base sequences of known genes
Identify specific genes
In 1998, the gene that mutates to cause prostate cancer was identified
Produce synthetic copies of genes
Insert genetic material into chromosomes that will help regulate cell function to make organisms genetically “better”

9. Viral DNA
Viral DNA (DNA from a virus) can also be used as a vector to carry recombinant DNA into a cell
When a virus containing recombinant DNA infects a cell, the viral DNA enters
Here it can direct the reproduction of many more viruses
Each virus derived from a viral vector contains a copy of the foreign gene, therefore viral vectors allow cloning of a particular gene

10. Viral Vectors Viral vectors are also used to create genomic libraries
A genomic library, or gene bank, is a collection of engineered viruses that carry all the genes of a species
Purpose:
Break up DNA into manageable chunks for research
Can analyze specific strands of DNA/amino acid sequences to determine their function, which can then be inserted into other cells
Stores all of the DNA for a species
It takes about 10 million viruses to carry all the genes of a mouse

11. Summary
Segments of DNA (particular genes) can be inserted into bacteria and the bacteria will produce these genes
If desired genes are used – like those that produce certain chemicals (vaccines, antibodies, etc.) then these proteins become much more available
Protein hormones like insulin (regulates blood-sugar levels) can be made using yeast cells
Interferon, a protein used in cancer treatments to help the immune system is now mass-produced in this way

12. Antibiotic Resistance
More and more bacteria are becoming resistant to our common antibiotics, and to make matters worse, more and more are becoming resistant to all known antibiotics
The problem is known as multi-resistance, and is generally described as one of the most significant future threats to public health
Antibiotic resistance can arise in bacteria in our environment and in our bodies
Antibiotic resistance can then be transferred to the bacteria that cause human diseases, even if the bacteria are not related to each other

13. Antibiotic Resistance
Antibiotic resistance-carrying plasmids from different bacteria can meet and exchange genetic material
The result is plasmids consisting of genes that have each been adapted to different bacterial species

14. Antibiotic Resistance
This facilitates further adaptation and mobility, and consequently the spread of antibiotic resistance between different bacterial species

15. Antibiotic Resistance
Widespread abuse of antibiotics, particularly in agriculture, is rapidly increasing the proliferation of multi-resistant bacteria

16. Antibiotic Resistance
Left unchecked, multi-resistant bacteria represent one of the greatest future health concerns in the world and could see the return of previously controlled diseases that affected humans in the past……
WITHOUT THE ABILITY TO STOP THEM
Currently, bacteria are developing multi-resistance faster than scientists can develop new antibiotics to control them

17. Are you scared yet?!