1. GENETIC ENGINEERING Human Cell DNA 1 Isolation
Cells are broken open using chemicals and enzymes releasing the DNA from the human cell and the plasmid from the bacterial cell.
Bacterial Cell
Plasmid
2 Cutting
Restriction enzymes recognise specific sites and cut the human DNA isolating the gene of interest. The same restriction enzyme is used to cut the plasmid.
Human DNA
Restriction enzyme
Restriction enzyme
Sticky end
3 Transformation
The gene of interest is inserted into the plasmid. The sticky ends of the human DNA complementary pair with the sticky ends of the plasmid.
Gene of interest
Sticky end
Recombinant Plasmid
An enzyme DNA ligase bonds the sticky ends of the human DNA and plasmid together
4. Expression
The recombinant plasmid is inserted back into a bacterial cell. The bacterial cell reproduces producing the polypeptide coded for by the donor DNA.
Bacterial cell reproduces by binary fission.
Kerry Teacher Design Team in association with the Biology Support Service, The Education Centre, Tralee