Biology · Principles and Processes in Biotechnology
हिन्दीA foreign DNA fragment is ligated into the BamHI site of plasmid pBR322. The transformants are selected on a medium containing ampicillin, and subsequently replica-plated onto a medium containing tetracycline. What will be the fate of the recombinant colonies?
Correct answer · Option 2
They will grow on ampicillin-containing medium but not on tetracycline-containing medium.
Explanation
Ligation at the BamHI site disrupts the tetracycline resistance gene (insertional inactivation), leaving the ampicillin resistance gene intact; hence recombinants grow on ampicillin but die on tetracycline.