1. TRANSFORMATION

2. What is Transformation?
When a cell takes up and expresses a new piece of genetic material—DNA— in order to change the organism’s traits
A gene is a piece of DNA which provides the instructions for making (coding for) a particular protein
One of the three processes(other being conjugation and transduction) by which exogenous materials may be introduced into a bacteria
DNA
Protein
Trait

3. Griffith’s Mysterious Transformation Experiment

4. Frederick Griffiths studied the R & S strains by injecting them into mice
S injected into mice -> pneumonia -> death
R injected into mice -> harmless
Also, boiled S injected into mice -> harmless (bacteria killed by boiling)

5. Griffiths did a strange experiment and got a strange result:
Boiled S + live R injected into mice -> pneumonia -> death
This was not expected because boiled S and live R were harmless by themselves
Took blood samples and found live S in the dead mice
Concluded that some factor, a "transforming principle", from the dead S had converted some R bacteria into S bacteria (a genetic change)

6. E. coli
Escherichia coli is the most common bacterium in the human gut. It has been extensively studied in the laboratory and is an important research organism for molecular biology. E. coli reproduce very rapidly; a single microscopic cell can divide to form a visible colony with millions of cells overnight. Like all bacteria, E. coli has no nuclear envelope surrounding the bacterial chromosome and thus no true nucleus. All of the genes required for basic survival and reproduction are found in the single chromosome.

7. Types Of Transformation
(Natural)
its a bacterial adaptation for DNA transfer , depends on expression of numerous bacterial genes.
bacteria must become COMPETENT, a special physiological state
Limited to about 67 prokaryotic species(7 diff phyla)

8. As an adaption for DNA repair Transformation is induced in Streptococcus pneumoniae by DNA damaging agents mitomycin C(crosslinking agent) and fluroquinole(breaks double bonds) Natural Competence 1% of bacteria is naturally capable of competence under lab conditions, by a process called horizontal gene transfer

9. Artificial Competence
Involves lab procedures that make the cell passively permeable to DNA
METHODS
Solution of divalent cations (calcium chloride) under cold conditions, before the application of heat shock
Electroporation, involves application of 10-20kv/cm, which creates holes in cell through which plasmid DNA enters

10. Basic Principle Of Transformation
Genes can be cut out of human, animal or plant DNA
placed inside bacteria and the bacteria will produce the “foreign” protein coded for by the gene.
For example, a healthy human gene for the hormone insulin can be put into bacteria. Under the right conditions, these bacteria can make authentic human insulin just as they would make their own proteins.

11. What is a plasmid? A plasmid is a small circle of DNA.
Ampicillin is an antibiotic; antibiotics prevent bacteria from growing.
*plasmids*
Bacterial
chromosomal DNA
Cell membrane

12. Transformation Procedure

13. TEST TIME!!!
Place the Stages of Transformation in Order:
C,B,D,E,A

14. Results

15. THANK YOU