BoardVitals Microbiology Test 2025 – 400 Free Practice Questions to Pass the Exam

Tetracycline is an antibiotic that works specifically by binding to the bacterial ribosome, thereby inhibiting protein synthesis. This mechanism is crucial because ribosomes are essential for translating messenger RNA (mRNA) into proteins within bacterial cells. By obstructing this process, tetracycline prevents bacteria from producing the proteins they need for growth and replication, ultimately leading to their death or stunted growth.

In contrast, the other antibiotics listed have different mechanisms of action. Penicillin targets the bacterial cell wall, interfering with peptidoglycan synthesis, which is vital for maintaining cell structure. Ciprofloxacin functions by inhibiting bacterial DNA gyrase and topoisomerase IV, disrupting DNA replication. Vancomycin also targets the cell wall, but specifically binds to precursors involved in peptidoglycan synthesis. Thus, tetracycline’s unique action on the ribosome differentiates it as the only antibiotic in this list that operates solely through that mechanism.