MOA of macrolides?

MOA of macrolides?

• A. Bind to 50S ribosomal subunit leading to inhibition of bacterial protein synthesis
• B. Inhibit DNA gyrase
• C. Inhibit cell wall synthesis
• D. Bind to 30S ribosomal subunit

Answer: (A)

Macrolides work by binding to the 50S ribosomal subunit, specifically interfacing with the 23S rRNA, and blocking the translocation step of protein synthesis. This prevents the ribosome from moving the growing polypeptide from the A site to the P site, stopping elongation and effectively halting bacterial protein production. This mechanism is distinct from drugs that inhibit DNA gyrase (which target DNA replication) or those that disrupt cell wall synthesis, and it is different from agents that bind the 30S subunit (which include drugs like aminoglycosides and tetracyclines). Macrolides are typically bacteriostatic, though they can be bactericidal for certain organisms at higher concentrations.

Macrolides work by binding to the 50S ribosomal subunit, specifically interfacing with the 23S rRNA, and blocking the translocation step of protein synthesis. This prevents the ribosome from moving the growing polypeptide from the A site to the P site, stopping elongation and effectively halting bacterial protein production.

This mechanism is distinct from drugs that inhibit DNA gyrase (which target DNA replication) or those that disrupt cell wall synthesis, and it is different from agents that bind the 30S subunit (which include drugs like aminoglycosides and tetracyclines). Macrolides are typically bacteriostatic, though they can be bactericidal for certain organisms at higher concentrations.