Antibiotics Targeting Bacterial Ribosomal Subunits: Mechanisms and Side Effects

Aminoglycosides

These irreversibly bind to the 30S subunit, causing it to malfunction. Unlike most others in this group, aminoglycosides are bactericidal.

Tetracyclines and Glycylcyclines

These bind reversibly to the 30S subunit. They function by blocking the attachment of tRNA, which effectively prevents the translation process from starting or continuing.

Macrolides

These bind reversibly to the 50S subunit and prevent the continuation of translation. They are often used as an alternative for patients with penicillin allergies.

Chloramphenicol

This medication binds to the 50S subunit to block translation. Due to rare but lethal side effects like aplastic anemia, it is generally used only as a last resort.

Lincosamides

These also bind the 50S subunit to prevent the continuation of translation.

Oxazolidinones

These interfere with the initiation of translation by binding to the 50S subunit.

Pleuromutilins

These prevent the formation of peptide bonds between amino acids during translation.

Streptogramins

These bind to the 50S subunit to inhibit translation. While individual components (like quinupristin and dalfopristin) are bacteriostatic, they become bactericidal when administered together.

30S Ribosomal Subunit

Targeted by aminoglycosides, tetracyclines, and glycylcyclines.

50S Ribosomal Subunit

Targeted by macrolides, chloramphenicol, lincosamides, oxazolidinones, and streptogramins.

Quinupristin and dalfopristin

Individual components of streptogramins that are bacteriostatic but become bactericidal when administered together.

Aplastic anemia

Rare but lethal side effect associated with the use of chloramphenicol.