23S ribosomal RNA of the 50S bacterial ribosomal subunit (23S rRNA)

Molecular Classification

Ribosomal RNA, Structural RNA, Component of ribosome, Other

Other Names

23S rRNA, 23S ribosomal RNA, Large subunit ribosomal RNA (bacterial)

Disease Roles

Infection (primary target of many antibacterial antibiotics)Other (mutations can confer antibiotic resistance but are not directly involved in diseases like cancer or inflammation)

23S ribosomal RNA of the 50S bacterial ribosomal subunit Overview

23S ribosomal RNA is a ~2900-nucleotide RNA molecule that constitutes the catalytic and structural core of the bacterial 50S large ribosomal subunit[1][3][7]. It forms the peptidyl transferase center, which catalyzes peptide bond formation, a fundamental process in protein synthesis[1][5]. The 23S rRNA is divided into six structural domains and interacts with both ribosomal proteins and transfer RNAs. It is the principal target of several classes of antibiotics—including macrolides, oxazolidinones, chloramphenicol, and lincosamides—which bind at the peptidyl transferase center and inhibit translation[2][4][6]. Mutations in 23S rRNA can confer resistance to these drugs and thereby limit their clinical efficacy. The 23S rRNA is indispensable for bacterial cell viability, making it a validated and essential therapeutic target[1][3][5].

Mechanism of Action

Inhibition of peptidyl transferase activity (blocking peptide bond formation); Inhibition of translocation of tRNA or mRNA on the ribosome; Disruption of ribosomal assembly or function

Biological Functions

Protein synthesis (catalysis of peptide bond formation)

Ribosome assembly

Translation (peptidyl transferase activity)

Regulation of translation fidelity

Disease Associations

Infection (primary target of many antibacterial antibiotics)

Other (mutations can confer antibiotic resistance but are not directly involved in diseases like cancer or inflammation)

Safety Considerations

Development of antibiotic resistance due to mutations in 23S rRNA
Off-target effects in mitochondrial ribosomes (in rare cases, as antibiotics may affect eukaryotic ribosomes with conserved regions)
Ribosomal dysregulation can impair global protein synthesis in bacteria, but targeting 23S rRNA is not associated with direct host toxicity

Interacting Drugs

Chloramphenicol

Macrolides (e.g., erythromycin, azithromycin)

Oxazolidinones (e.g., linezolid)

Lincosamides (e.g., clindamycin)

Streptogramins

Pleuromutilins

Cethromycin

Associated Biomarkers

Biomarker
Mutations in specific 23S rRNA positions (A2058G, A2059G, others in E. coli numbering) are markers of resistance to macrolides, lincosamides, and streptogramins
Methylation status of certain nucleotides (e.g., U2552)
Presence of specific rRNA mutations can be used to detect or predict antibiotic resistance phenotypes