Question

BamH1 is a restriction enzyme which recognizes the sequence 5'-GGATCC-3'. The restriction activity of this enzyme is between G and G.

1. Construct the palindrome for the above sequence.
2. Draw a labeled diagram to show the formation of recombinant DNA (rDNA) using BamH1.
3. PBR322 is a plasmid that has a restriction site for this enzyme at the tetracycline-resistant gene. If BamH1 were to be used, how will it impact the response of the transformant with rDNA to the antibiotics ampicillin and tetracycline? Justify.

Answer 1

1. 5'-GGATCC-3'.
   3'-CCTAGG-5'
2. 
   
3. If BamHI is used to insert the gene of interest into pBR322 at the tetracycline-resistance (tet^R) gene site, the tet^R gene gets disrupted due to insertional inactivation. Therefore, the transformant containing recombinant DNA will survive in the presence of ampicillin because the ampicillin-resistance (amp^R) gene remains intact, but it will not survive in the presence of tetracycline because the tetracycline-resistance gene becomes non-functional after the insertion.