Question

Which of the following enzymes will be used to insert genes at tet^R site of cloning vector pBR322-Sal 1 , Eco R 1 or Hind 3.why? how will the insertion affect the bacteria into which this rDNA is introduced?

Answer 1

Dear student,
Restriction enzyme Sa/1 can be used to insert foreign gene at the tet^R​ site of cloning vector pBR322 because restriction site for this enzyme is present at the tet^R​ site of pBR322.
Since the foreign gene is inserted into the tet^R​ site therefore the tetracycline resistance property will be lost in the recombinant plasmid. The insertion can affect the bacteria because the inserted gene will not grow in medium containing tetracycline because tetracycline resistance is lost.

Regards