Question

Which one of the following compounds is NOT a translation inhibitor?

• A. Chloramphenicol
• B. Cycloheximide
• C. Puromycin
• D. Rifampicin

Hint:

Translation inhibitors block protein synthesis by targeting different steps in the process, but Rifampicin inhibits transcription, not translation.

Answer 1

The Correct Option is D

Step 1: Understanding Translation Inhibition.
Translation inhibitors are compounds that block protein synthesis by inhibiting the translation process at various stages. Some antibiotics, like chloramphenicol, cycloheximide, and puromycin, act by binding to the ribosome and blocking translation.
Step 2: Analyzing the Options.
- (A) Chloramphenicol: This is a translation inhibitor. It inhibits the peptidyl transferase activity of the ribosome, thereby blocking protein synthesis.
- (B) Cycloheximide: This is a translation inhibitor. It inhibits protein synthesis in eukaryotes by blocking the translocation step of the ribosome.
- (C) Puromycin: This is a translation inhibitor. It mimics the aminoacyl-tRNA and causes premature chain termination during translation.
- (D) Rifampicin: This is NOT a translation inhibitor. Rifampicin inhibits RNA polymerase and thus prevents transcription, not translation.
Step 3: Conclusion.
The correct answer is (D) Rifampicin, as it inhibits transcription, not translation.