KCET2026BiologyBiotechnology - Principles and Processes
Given below are two statements. Statement-I: Restriction enzyme BamHI has its recognition site in R^ tet region of pBR322. Statement-II: E.coli having pBR322 with a desired DNA if inserted at BamHI site can grow in medium containing tetracycline. In the light of the above statements, choose the correct answer from the options given below.
Options
- ABoth Statement I and Statement II are true
- BBoth Statement I and Statement II are false
- CStatement I is true, but Statement II is false
- DStatement I is false, but Statement II is true
Correct answer
C. Statement I is true, but Statement II is false
Step-by-step solution
In the plasmid pBR322, the tetracycline resistance gene ( tet^ R ) contains recognition sites for the restriction enzymes BamHI and SalI. Therefore, Statement-I is true. When a desired DNA fragment is inserted at the BamHI site, the tetracycline resistance gene gets disrupted due to insertional inactivation. As a result, the recombinant plasmid loses its resistance to tetracycline. Thus, E. coli host cells containing this recombinant pBR322 will not be able to grow in a medium containing tetracycline. Therefore, St