Powerpoint pressentation on Identification of recombinants in bacterial cells.

1. Identification Of Recombinants

2. i-Plating onto a selective medium
Enables transformants to be distinguished from non-transformants.

3. Insertional inactivation of an antibiotic
resistance gene
 pBR322 has several unique restriction sites that can be used to open up
the vector before insertion of a new DNA fragment
 BamHI cuts pBR322 at just one position, within the cluster of genes that
code for resistance to tetracycline
 Cells containing this recombinant pBR322 molecule are still resistant to
ampicillin, but sensitive to tetracycline
Transformation
Plating onto
Ampicillin Agar
Replica Plating on
Agar medium
containing
Tetracycline

5. ii-Insertional inactivation of lacZ′
An example is pUC8 (Figure 5.9a), which carries the ampicillin resistance
gene and a gene called lacZ’, which codes for part of the enzyme b-
galactosidase.