Modulating the activity of the peptidyl transferase center of the ribosome.
The peptidyl transferase (PT) center of the ribosome catalyzes two nucleophilic reactions, peptide bond formation between aminoacylated tRNA substrates and, together with release factor, peptide release. Structure and function of the PT center are modulated by binding of aminoacyl-tRNA or release factor, thus providing the basis for the specificity of catalysis. Another way by which the function of the PT center is controlled is signaling from the peptide exit tunnel. The SecM nascent peptide induces ribosome stalling, presumably by inhibition of peptide bond formation. Similarly, the release factor-induced hydrolytic activity of the PT center can be suppressed by the TnaC nascent peptide contained in the exit tunnel. Thus, local and long-range conformational rearrangements can lead to changes in the reaction specificity and catalytic activity of the PT center.
Beringer
Malte
M
Institute of Physical Biochemistry, University of Witten/Herdecke, 58448 Witten, Germany. malte.beringer@crg.es
D020134:Catalytic Domain / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism; D006868:Hydrolysis; D008954:Models, Biological; D010458:Peptidyl Transferases / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000201:enzymology* / Q000378:metabolism; D015398:Signal Transduction; D014157:Transcription Factors / Q000378:metabolism
D029968:Escherichia coli Proteins; C497347:SecM protein, E coli; D014157:Transcription Factors; C081473:tnaC protein, E coli; D010458:Peptidyl Transferases