GENETIC RECOMBINATION
By
Dr. Nessrin Ghazi AL-Abdallat
Lecturer of Microbiology
Definition
 A method to isolate genes coding for certain
proteins and join them together to form new
combinations.
 Also called:
 Gene cloning.
 Recombinant DNA technology.
 Genetic engineering.
Summary
 Separation of the required gene by restriction
endonuclease enzyme.
 Cutting of the cloning vector (like plasmid) by the same
restriction enzyme.
 Adding the gene to the cloning vector in the presence of
ligase enzyme. This is called recombination.
 Introduction of the gene-vector complex into the host
cell by transformation.
 Inside the host cell like E. coli or yeast cell, the gene will
replicate with the plasmid producing so many copies.
Restriction endonuclease enzymes
These are enzymes derived from bacteria or
fungi that can recognize and cut DNA molecules
at specific sites (specific base sequence).
They are named according to the their source.
For example: EcoRI enzyme is derived from E.
coli and recognize the sequence GAATTC
Molecular cloning vectors
These are carriers used to carry and introduce
specific genes into the host cells.
They are either:
1) Plasmids.
2) Bacteriophages.
3) Cosmids: circular DNA molecules constructed from
plasmid DNA + phage DNA. It can carry larger genes
that can not be carried by plasmid or bacteriophage.
Gene cloning
Insulin production by gene cloning
BEST WISHES