Publications
2007
Roy H, Becker H D, Mazauric M H, Kern D
Structural elements defining elongation factor Tu mediated suppression of codon ambiguity Article de journal
Dans: Nucleic Acids Res, vol. 35, no. 10, p. 3420-3430, 2007, ISBN: 17478519, (1362-4962 (Electronic) Journal Article Research Support, Non-U.S. Gov't).
Résumé | Liens | BibTeX | Étiquettes: Amino Acyl/*chemistry/metabolism RNA, Asn/*chemistry/metabolism RNA, Asp/chemistry/metabolism Thermus thermophilus/genetics *Transfer RNA Aminoacylation, KERN Base Pairing *Codon Escherichia coli Proteins/metabolism Models, Molecular Peptide Elongation Factor Tu/*chemistry/metabolism Protein Binding RNA, Transfer, Unité ARN
@article{,
title = {Structural elements defining elongation factor Tu mediated suppression of codon ambiguity},
author = {H Roy and H D Becker and M H Mazauric and D Kern},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=17478519},
isbn = {17478519},
year = {2007},
date = {2007-01-01},
journal = {Nucleic Acids Res},
volume = {35},
number = {10},
pages = {3420-3430},
abstract = {In most prokaryotes Asn-tRNA(Asn) and Gln-tRNA(Gln) are formed by amidation of aspartate and glutamate mischarged onto tRNA(Asn) and tRNA(Gln), respectively. Coexistence in the organism of mischarged Asp-tRNA(Asn) and Glu-tRNA(Gln) and the homologous Asn-tRNA(Asn) and Gln-tRNA(Gln) does not, however, lead to erroneous incorporation of Asp and Glu into proteins, since EF-Tu discriminates the misacylated tRNAs from the correctly charged ones. This property contrasts with the canonical function of EF-Tu, which is to non-specifically bind the homologous aa-tRNAs, as well as heterologous species formed in vitro by aminoacylation of non-cognate tRNAs. In Thermus thermophilus that forms the Asp-tRNA(Asn) intermediate by the indirect pathway of tRNA asparaginylation, EF-Tu must discriminate the mischarged aminoacyl-tRNAs (aa-tRNA). We show that two base pairs in the tRNA T-arm and a single residue in the amino acid binding pocket of EF-Tu promote discrimination of Asp-tRNA(Asn) from Asn-tRNA(Asn) and Asp-tRNA(Asp) by the protein. Our analysis suggests that these structural elements might also contribute to rejection of other mischarged aa-tRNAs formed in vivo that are not involved in peptide elongation. Additionally, these structural features might be involved in maintaining a delicate balance of weak and strong binding affinities between EF-Tu and the amino acid and tRNA moieties of other elongator aa-tRNAs.},
note = {1362-4962 (Electronic)
Journal Article
Research Support, Non-U.S. Gov't},
keywords = {Amino Acyl/*chemistry/metabolism RNA, Asn/*chemistry/metabolism RNA, Asp/chemistry/metabolism Thermus thermophilus/genetics *Transfer RNA Aminoacylation, KERN Base Pairing *Codon Escherichia coli Proteins/metabolism Models, Molecular Peptide Elongation Factor Tu/*chemistry/metabolism Protein Binding RNA, Transfer, Unité ARN},
pubstate = {published},
tppubtype = {article}
}
In most prokaryotes Asn-tRNA(Asn) and Gln-tRNA(Gln) are formed by amidation of aspartate and glutamate mischarged onto tRNA(Asn) and tRNA(Gln), respectively. Coexistence in the organism of mischarged Asp-tRNA(Asn) and Glu-tRNA(Gln) and the homologous Asn-tRNA(Asn) and Gln-tRNA(Gln) does not, however, lead to erroneous incorporation of Asp and Glu into proteins, since EF-Tu discriminates the misacylated tRNAs from the correctly charged ones. This property contrasts with the canonical function of EF-Tu, which is to non-specifically bind the homologous aa-tRNAs, as well as heterologous species formed in vitro by aminoacylation of non-cognate tRNAs. In Thermus thermophilus that forms the Asp-tRNA(Asn) intermediate by the indirect pathway of tRNA asparaginylation, EF-Tu must discriminate the mischarged aminoacyl-tRNAs (aa-tRNA). We show that two base pairs in the tRNA T-arm and a single residue in the amino acid binding pocket of EF-Tu promote discrimination of Asp-tRNA(Asn) from Asn-tRNA(Asn) and Asp-tRNA(Asp) by the protein. Our analysis suggests that these structural elements might also contribute to rejection of other mischarged aa-tRNAs formed in vivo that are not involved in peptide elongation. Additionally, these structural features might be involved in maintaining a delicate balance of weak and strong binding affinities between EF-Tu and the amino acid and tRNA moieties of other elongator aa-tRNAs.