Title of article :
An Uncharged Amine in the Transition State of the Ribosomal Peptidyl Transfer Reaction Original Research Article
Author/Authors :
David A. Kingery، نويسنده , , Emmanuel Pfund، نويسنده , , Rebecca M. Voorhees، نويسنده , , Kensuke Okuda، نويسنده , , Ingo Wohlgemuth، نويسنده , , David E. Kitchen، نويسنده , , Marina V. Rodnina، نويسنده , , Scott A. Strobel، نويسنده ,
Issue Information :
ماهنامه با شماره پیاپی سال 2008
Pages :
8
From page :
493
To page :
500
Abstract :
The ribosome has an active site comprised of RNA that catalyzes peptide bond formation. To understand how RNA promotes this reaction requires a detailed understanding of the chemical transition state. Here, we report the Brønsted coefficient of the α-amino nucleophile with a series of puromycin derivatives. Both 50S subunit- and 70S ribosome-catalyzed reactions displayed linear free-energy relationships with slopes close to zero under conditions where chemistry is rate limiting. These results indicate that, at the transition state, the nucleophile is neutral in the ribosome-catalyzed reaction, in contrast to the substantial positive charge reported for typical uncatalyzed aminolysis reactions. This suggests that the ribosomal transition state involves deprotonation to a degree commensurate with nitrogen-carbon bond formation. Such a transition state is significantly different from that of uncatalyzed aminolysis reactions in solution.
Journal title :
Chemistry and Biology
Serial Year :
2008
Journal title :
Chemistry and Biology
Record number :
1159540
Link To Document :
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