This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Cruz-Vera, L. R.
Right arrow Articles by Yanofsky, C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Cruz-Vera, L. R.
Right arrow Articles by Yanofsky, C.

 Previous Article  |  Next Article 

Journal of Bacteriology, April 2007, p. 3140-3146, Vol. 189, No. 8
0021-9193/07/$08.00+0     doi:10.1128/JB.01869-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Ribosomal Features Essential for tna Operon Induction: Tryptophan Binding at the Peptidyl Transferase Center{triangledown}

Luis R. Cruz-Vera,1 Aaron New,2 Catherine Squires,2 and Charles Yanofsky1*

Department of Biological Sciences, Stanford University, Stanford, California 94305,1 Department of Molecular Biology and Microbiology, School of Medicine, Tufts University, Boston, Massachusetts 021112

Received 12 December 2006/ Accepted 31 January 2007

Features of the amino acid sequence of the TnaC nascent peptide are recognized by the translating ribosome. Recognition leads to tryptophan binding within the translating ribosome, inhibiting the termination of tnaC translation and preventing Rho-dependent transcription termination in the tna operon leader region. It was previously shown that inserting an adenine residue at position 751 or introducing the U2609C change in 23S rRNA or introducing the K90W replacement in ribosomal protein L22 prevented tryptophan induction of tna operon expression. It was also observed that an adenine at position 752 of 23S rRNA was required for induction. In the current study, the explanation for the lack of induction by these altered ribosomes was investigated. Using isolated TnaC-ribosome complexes, it was shown that although tryptophan inhibits puromycin cleavage of TnaC-tRNAPro with wild-type ribosome complexes, it does not inhibit cleavage with the four mutant ribosome complexes examined. Similarly, tryptophan prevents sparsomycin inhibition of TnaC-tRNAPro cleavage with wild-type ribosome complexes but not with these mutant ribosome complexes. Additionally, a nucleotide located close to the peptidyl transferase center, A2572, which was protected from methylation by tryptophan with wild-type ribosome complexes, was not protected with mutant ribosome complexes. These findings identify specific ribosomal residues located in the ribosome exit tunnel that recognize features of the TnaC peptide. This recognition creates a free tryptophan-binding site in the peptidyl transferase center, where bound tryptophan inhibits peptidyl transferase activity.

* Corresponding author. Mailing address: Department of Biological Sciences, Stanford University, Stanford, CA 94305. Phone: (650) 725-1835. Fax: (650) 725-8221. E-mail: yanofsky{at}cmgm.stanford.edu

{triangledown} Published ahead of print on 9 February 2007.

Journal of Bacteriology, April 2007, p. 3140-3146, Vol. 189, No. 8
0021-9193/07/$08.00+0     doi:10.1128/JB.01869-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Cruz-Vera, L. R., Yang, R., Yanofsky, C. (2009). Tryptophan Inhibits Proteus vulgaris TnaC Leader Peptide Elongation, Activating tna Operon Expression. J. Bacteriol. 191: 7001-7006 [Abstract] [Full Text]  
  • Yang, R., Cruz-Vera, L. R., Yanofsky, C. (2009). 23S rRNA Nucleotides in the Peptidyl Transferase Center Are Essential for Tryptophanase Operon Induction. J. Bacteriol. 191: 3445-3450 [Abstract] [Full Text]  
  • Wohlgemuth, I., Brenner, S., Beringer, M., Rodnina, M. V. (2008). Modulation of the Rate of Peptidyl Transfer on the Ribosome by the Nature of Substrates. J. Biol. Chem. 283: 32229-32235 [Abstract] [Full Text]  
  • Cruz-Vera, L. R., Yanofsky, C. (2008). Conserved Residues Asp16 and Pro24 of TnaC-tRNAPro Participate in Tryptophan Induction of tna Operon Expression. J. Bacteriol. 190: 4791-4797 [Abstract] [Full Text]  
  • Stewart, V. (2008). The Ribosome: a Metabolite-Responsive Transcription Regulator. J. Bacteriol. 190: 4787-4790 [Full Text]  
  • Beringer, M. (2008). Modulating the activity of the peptidyl transferase center of the ribosome. RNA 14: 795-801 [Abstract] [Full Text]  
  • Onouchi, H., Haraguchi, Y., Nakamoto, M., Kawasaki, D., Nagami-Yamashita, Y., Murota, K., Kezuka-Hosomi, A., Chiba, Y., Naito, S. (2008). Nascent Peptide-Mediated Translation Elongation Arrest of Arabidopsis thaliana CGS1 mRNA Occurs Autonomously. Plant Cell Physiol 49: 549-556 [Abstract] [Full Text]  
  • Yanofsky, C. (2007). RNA-based regulation of genes of tryptophan synthesis and degradation, in bacteria. RNA 13: 1141-1154 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»