23S

Pseudoknot of the domain G(G12) of 23S ribosomal RNA
Predicted secondary structure and sequence conservation of PK-G12rRNA
Identifiers
Symbol	PK-G12rRNA
Rfam	RF01118
Other data
RNA type	Gene; rRNA
Domain(s)	Bacteria
SO	0001263

The 23S rRNA is a 2904 nt long (in E. coli) component of the large subunit (50S) of the bacterial ribosome. The ribosomal peptidyl transferase activity resides in domain V of this rRNA, and this domain is the most common binding site for antibiotics that inhibit translation. A well-known member of this antibiotic class, chloramphenicol, acts by inhibiting peptide bond formation, with recent 3D-structural studies showing two different binding sites depending on the species of ribosome. Linezolid and quinupristin-dalfopristin also bind to the 23S rRNA, and cross-resistance has been demonstrated between these antibiotics.