Which molecular event best describes the bactericidal action of gentamicin?

• A Binding to the 23S rRNA component of the 50S subunit and blocking translocation
• B Binding to the 30S subunit, causing misreading of the mRNA codon sequence ✓
• C Blocking peptidyl transferase at the A site of the 50S subunit
• D Preventing formation of the 70S initiation complex by binding IF-2

Explanation

Aminoglycosides bind irreversibly to the 30S ribosomal subunit, specifically near the A site, and cause misreading of codons so that incorrect amino acids are incorporated into the growing peptide. This produces nonfunctional proteins and bacterial death. Option D describes the action of linezolid at 50S initiation interference territory incorrectly, while option A describes macrolides and chloramphenicol blocks peptidyl transferase.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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