Cutibacterium acnes 23S ribosomal RNA (23S rRNA)

The Cutibacterium acnes 23S ribosomal RNA (23S rRNA) is a fundamental structural and catalytic component of the 50S large ribosomal subunit in the Gram-positive bacterium C. acnes. It is essential for bacterial viability as it forms the peptidyl transferase center (PTC), which catalyzes peptide bond formation, and the nascent peptide exit tunnel (NPET) through which growing proteins pass (Lomakin et al., 2024). C. acnes is a key commensal of the human skin but acts as an opportunistic pathogen in the development of acne vulgaris and medical device-related infections (NIH, 2022). Consequently, its 23S rRNA is a major therapeutic target for several antibiotic classes, including macrolides (e.g., erythromycin) and lincosamides (e.g., clindamycin), which bind to the PTC or NPET to halt protein synthesis (Dermatology Times, 2025). Recent structural studies using cryo-electron microscopy have also revealed that the narrow-spectrum tetracycline sarecycline possesses a unique second binding site on the C. acnes 23S rRNA, contributing to its efficacy (Nucleic Acids Research, 2024). However, the clinical utility of these drugs is increasingly threatened by resistance, primarily mediated by point mutations in the 23S rRNA gene (such as A2241G) or enzymatic methylation by erm genes (Journal of Antimicrobial Chemotherapy, 2026). Understanding the molecular interactions at this site is critical for the design of next-generation antimicrobials that can overcome existing resistance mechanisms.

Other names

Propionibacterium acnes 23S ribosomal RNA50S ribosomal 23S rRNAPeptidyl transferase centerPTC

Inhibition of bacterial protein synthesis by binding to the 50S ribosomal subunit, specifically the 23S rRNA, which blocks the peptidyl transferase center or the nascent peptide exit tunnel, thereby preventing peptide bond formation or polypeptide elongation.