Which antibiotic class is generally effective against Mycoplasma pneumoniae due to the absence of a cell wall?

• A. Beta-lactam
• B. Aminoglycoside
• C. Macrolide
• D. Sulfonamide

Answer: (C)

Mycoplasma pneumoniae lacks a peptidoglycan cell wall, so drugs that disrupt cell wall synthesis won’t work. Macrolides are effective because they inhibit bacterial protein synthesis by binding the 50S ribosomal subunit, blocking translocation and preventing growth of this organism. This makes macrolides the preferred treatment for Mycoplasma-related atypical pneumonia. In contrast, agents that rely on the cell wall target (like beta-lactams) are ineffective here, and other classes such as sulfonamides don’t address the organism’s weakness.