Question

Which of the following changes in a vector is used to increase the yield of protein produced in recombinant protein synthesis?

• A. Inducible promoter
• B. Genes for protease inhibitors
• C. Translation initiation
• D. Translation and transcription termination

Hint:

Yield depends on a controllable switch that turns transcription on at high cell density.

Answer 1

The Correct Option is A

Step 1: Understand the goal. In recombinant protein production, a high-level, controllable expression of the cloned gene is needed to maximize yield.
Step 2: Identify the key vector element. The promoter drives transcription of the inserted gene, so the amount of protein made depends heavily on promoter strength and control.
Step 3: Explain why an inducible promoter helps. An inducible promoter (for example the lac/tac promoter switched on by IPTG) lets the host grow first without burdening it with foreign protein, and then transcription is strongly turned on at high cell density, giving a large burst of product and reducing toxicity to the host.
Step 4: Exclude the others. Protease inhibitor genes only protect against degradation, translation initiation and termination signals are necessary but are not the principal lever for increasing yield.
Conclusion: An inducible promoter is used to boost recombinant protein yield, so the correct answer is option 1.