Bedaquiline is used in MDR-TB regimens. Its unique mechanism targets which bacterial component?

• A Mycobacterial InhA (enoyl-ACP reductase) involved in mycolic acid synthesis
• B Mycobacterial ATP synthase subunit c (F0 component), depleting intracellular ATP ✓
• C Decaprenyl-phosphate arabinose synthesis pathway disrupting cell wall arabinogalactan
• D 30S ribosomal RNA at the 16S decoding site causing mistranslation

Explanation

Bedaquiline (a diarylquinoline) is the first new anti-TB drug with a novel mechanism in decades. It specifically inhibits the mycobacterial F0F1 ATP synthase by binding to subunit c of the F0 rotor, blocking proton translocation and ATP synthesis. This depletes intracellular ATP, which is lethal for both replicating and non-replicating (persistent) mycobacteria. Option A describes isoniazid/ethionamide (InhA); option C describes ethambutol (arabinogalactan); option D describes aminoglycosides.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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