Ribosomal 50S subunit (50S subunit)

The ribosomal 50S subunit is the larger component of the prokaryotic 70S ribosome (found in bacteria and archaea) and is essential for protein synthesis. It consists of ribosomal RNA (23S and 5S rRNA) and about 31 proteins, forming a complex structure that catalyzes peptide bond formation (peptidyl transferase activity) during the elongation phase of translation. Functionally, the 50S subunit is targeted by several classes of antibiotics, including macrolides, chloramphenicol, and oxazolidinones, many of which inhibit bacterial growth by interfering with protein synthesis. Structural differences between bacterial and archaeal 50S subunits underlie differences in antibiotic sensitivity. The subunit’s integrity and correct assembly are maintained by a coordinated sequence of protein and RNA interactions, with specialized assembly factors ensuring only fully mature subunits participate in translation. The 50S ribosomal subunit is a critical therapeutic target for antibacterial drugs and a molecular biomarker to differentiate bacterial infection[1][3][4][7].

Other names

Prokaryotic large ribosomal subunitlarge ribosomal subunit (prokaryote)50S large subunit50S ribosome subunit

Inhibition of protein synthesis by binding to 50S and blocking peptide elongation; Inhibition of peptidyl transferase activity, preventing peptide bond formation; Disruption of tRNA translocation or exit site binding; Inhibition of ribosomal assembly