title: Modification of 50S ribosomal subunits with N-bromosuccinimide.
abstract: The 50S subunits of Escherichia coli ribosomes were modified with the tryptophan reagent N-bromosuccinimide, and the sulfhydryl groups, the modification of which is accompanied by stimulation of polypeptide synthesis (López-Rivas, A. et al. (1978) Eur. J. Biochem. 92, 121), were regenerated by incubation with simple thiols. This treatment inactivates poly(U)-dependent polyphenylalanine synthesis, peptidyl transferase and elongation factor G-dependent GTPase. Incubation with proteins from untreated 70S ribosomes produces partial reactivation of polyphenylalanine synthesis and GTPase activity. Modification is accompanied by loss of 4-5 tryptophan residues per subunit.
mesh_terms: D001974:Bromosuccinimide / Q000494:pharmacology*; D055598:Chemical Phenomena; D002621:Chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D012269:Ribosomal Proteins / Q000032:analysis / Q000096:biosynthesis; D012270:Ribosomes / Q000187:drug effects*; D013388:Succinimides / Q000494:pharmacology*; D014364:Tryptophan
chemical_list: D012269:Ribosomal Proteins; D013388:Succinimides; D014364:Tryptophan; D001974:Bromosuccinimide