Antimicrobials and Resistance · USMLE Step 1

A patient taking macrolides develops prolonged QT interval. What is the primary mechanism of macrolide action?

  1. Blocks the 30S ribosomal subunit
  2. Inhibits translocation at 50S subunit
  3. Inhibits cell wall cross-linking
  4. Inhibits dihydropteroate synthase
Show answer and explanation

Correct answer: Inhibits translocation at 50S subunit

Macrolides bind the 50S subunit and prevent translocation during protein synthesis.

Difficulty: Medium Question 15 of 20

Practice all 20 Antimicrobials and Resistance questions

Keep practicing

More Antimicrobials and Resistance questions