Instruction of Translating Ribosome by Nascent Peptide

摘要: Expression of the tryptophanase operon Escherichia coli is regulated by catabolite repression and tryptophan-induced transcription antitermination. An induction site activated l-tryptophan created in translating ribosome during synthesis TnaC, 24-residue leader peptide. Replacing tnaC stop codon with a tryptophan allows tryptophan-charged transfer RNA to substitute for as inducer. This suggests that ribosomal A occupied tryptophanyl moiety charged induction. The location tryptophan-12 nascent TnaC peptide exit tunnel was crucial These results show sequence can influence translation continuation termination within ribosome.