60S ribosomal subunit peptidyltransferase

The 60S ribosomal subunit peptidyltransferase is an enzymatic center within the large (60S) subunit of eukaryotic ribosomes, primarily formed by ribosomal RNA (rRNA), making it a ribozyme rather than a classical protein enzyme[1][4]. Its core function is to catalyze peptide bond formation between amino acids during translation, the central reaction of protein synthesis[4][5]. This process occurs at the peptidyl transferase center (PTC), where the growing polypeptide chain is transferred from the peptidyl-tRNA in the P-site to the aminoacyl-tRNA in the A-site, extending the nascent protein[1][5]. The structure of the PTC is highly conserved across all domains of life, with the catalytic activity residing mainly in the rRNA component, although ribosomal proteins and modifications contribute to its stability and regulation[4][2]. The 60S ribosomal subunit, and thus its peptidyltransferase, is a target for certain antibiotics and inhibitors (e.g., cycloheximide), which block protein synthesis by interfering with the PTC[2]. The 60S subunit also contains other functional sites essential for translation, including the polypeptide exit tunnel, GTPase-associated center, and sites for tRNA binding (A-, P-, and E-sites)[1][4]. Disruption of peptidyltransferase function is generally not a common therapeutic strategy in humans due to its essential role in all cells, but it remains a key antibiotic target in infectious disease and has been explored in cancer therapy. The presence of numerous rRNA modifications around the PTC may also have important roles in maintaining structural integrity and regulating activity, but these are less well understood at the functional level[4].

Other names

Ribosomal peptidyl transferasePeptidyl transferase centerPTCRibosomal large subunit peptidyltransferase

Inhibition of peptide bond formation, Translation inhibition