Publication Date:
2009-11-26
Description:
Expression of the Escherichia coli tryptophanase operon depends on ribosome stalling during translation of the upstream TnaC leader peptide, a process for which interactions between the TnaC nascent chain and the ribosomal exit tunnel are critical. We determined a 5.8 angstrom-resolution cryo-electron microscopy and single-particle reconstruction of a ribosome stalled during translation of the tnaC leader gene. The nascent chain was extended within the exit tunnel, making contacts with ribosomal components at distinct sites. Upon stalling, two conserved residues within the peptidyltransferase center adopted conformations that preclude binding of release factors. We propose a model whereby interactions within the tunnel are relayed to the peptidyltransferase center to inhibit translation. Moreover, we show that nascent chains adopt distinct conformations within the ribosomal exit tunnel.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2920484/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2920484/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Seidelt, Birgit -- Innis, C Axel -- Wilson, Daniel N -- Gartmann, Marco -- Armache, Jean-Paul -- Villa, Elizabeth -- Trabuco, Leonardo G -- Becker, Thomas -- Mielke, Thorsten -- Schulten, Klaus -- Steitz, Thomas A -- Beckmann, Roland -- GM022778/GM/NIGMS NIH HHS/ -- P41 RR005969/RR/NCRR NIH HHS/ -- P41 RR005969-19/RR/NCRR NIH HHS/ -- P41-RR05969/RR/NCRR NIH HHS/ -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2009 Dec 4;326(5958):1412-5. doi: 10.1126/science.1177662. Epub 2009 Oct 29.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Gene Center and Center for Integrated Protein Science Munich (CIPSM), Department for Chemistry and Biochemistry, University of Munich, Feodor-Lynen-Strasse 25, 81377 Munich, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19933110" target="_blank"〉PubMed〈/a〉
Keywords:
Binding Sites
;
Cryoelectron Microscopy
;
Escherichia coli/*genetics/metabolism
;
Escherichia coli Proteins/*chemistry/genetics/*metabolism/ultrastructure
;
Gene Expression Regulation, Bacterial
;
Image Processing, Computer-Assisted
;
Models, Biological
;
Models, Molecular
;
Operon
;
Peptidyl Transferases/metabolism
;
*Protein Biosynthesis
;
Protein Conformation
;
RNA-Binding Proteins/chemistry/metabolism/ultrastructure
;
Ribosomal Proteins/chemistry/metabolism/ultrastructure
;
Ribosomes/*metabolism/ultrastructure
;
Tryptophanase/biosynthesis/*genetics
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
