title: Reconstruction of peptidyltransferase activity on 50S and 70S ribosomal particles by peptide fragments of protein L16.
abstract: Ribosomal protein L16 was digested with Staphylococcus aureus protease V8 and the resulting peptides were separated by reversed-phase high-performance liquid chromatography. One of the fragments, identified by sequence analysis as the N-terminal peptide of L16, was shown to exhibit partial peptide-bond-formation and transesterification activities of peptidyltransferase upon reconstitution with L16-depleted 50S core particles. However, several proteins enhanced these activities. L15 increased both reactions when added to the reconstitution mixture, suggesting a limited capacity of the L16 peptide to incorporate into 50S core particles. In contrast, the interaction of L11 with the N-terminal peptide stimulated the transesterification reaction but not the peptide-bond-forming activity of ribosomes, indicating a different topological domain for these reactions. Also, EF-P, a soluble protein which reconstructs the peptide-bond formation and transesterification reactions on 70S ribosomes, stimulated both peptidyltransferase activities exhibited by the L16 N-terminal peptide.
mesh_terms: D000217:Acyltransferases / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D010450:Endopeptidases / Q000378:metabolism; D004926:Escherichia coli; D010446:Peptide Fragments / Q000494:pharmacology; D010458:Peptidyl Transferases / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000494:pharmacology*; D012270:Ribosomes / Q000187:drug effects / Q000201:enzymology*; D012697:Serine Endopeptidases
chemical_list: D010446:Peptide Fragments; D012269:Ribosomal Proteins; C027937:ribosomal protein L16; D000217:Acyltransferases; D010458:Peptidyl Transferases; D010450:Endopeptidases; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase