The antibiotic that inhibits protein synthesis by premature chain termination and which structurally resembles an aminoacyl t-RNA is –
**Core Concept**
The question is testing the student's knowledge of antibiotics that inhibit protein synthesis, specifically those that cause premature chain termination. The correct answer is a type of antibiotic that structurally resembles an aminoacyl t-RNA, which is a crucial component in the process of protein synthesis.
**Why the Correct Answer is Right**
The correct answer is an aminoglycoside antibiotic, such as Gentamicin or Streptomycin. Aminoglycosides work by binding to the 30S subunit of the bacterial ribosome, mimicking the structure of an aminoacyl t-RNA. This causes the ribosome to misread the mRNA sequence, leading to premature chain termination and ultimately, bacterial cell death.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it is not an aminoglycoside antibiotic. Aminoglycosides are a class of antibiotics that specifically inhibit protein synthesis by causing premature chain termination.
* **Option B:** This option is incorrect because it is a beta-lactam antibiotic, which works by inhibiting cell wall synthesis, not protein synthesis.
* **Option C:** This option is incorrect because it is an antibiotic that works by inhibiting protein synthesis by binding to the 50S subunit of the ribosome, not the 30S subunit.
**Clinical Pearl / High-Yield Fact**
Aminoglycosides are ototoxic, meaning they can cause damage to the inner ear and lead to hearing loss or tinnitus. This is a critical consideration when prescribing these antibiotics, especially for patients with pre-existing hearing impairments.
**Correct Answer: C. Aminoglycosides, such as Gentamicin or Streptomycin.**