4UY8
Molecular basis for the ribosome functioning as a L-tryptophan sensor - Cryo-EM structure of a TnaC stalled E.coli ribosome
Summary for 4UY8
| Entry DOI | 10.2210/pdb4uy8/pdb |
| EMDB information | 2773 |
| Descriptor | 50S RIBOSOMAL PROTEIN L32, RRNA-23S RIBOSOMAL RNA, RRNA-5S RIBOSOMAL RNA, ... (39 entities in total) |
| Functional Keywords | ribosome, tnac, translation regulation |
| Biological source | ESCHERICHIA COLI More |
| Total number of polymer chains | 35 |
| Total formula weight | 1376255.87 |
| Authors | Bischoff, L.,Berninghausen, O.,Beckmann, R. (deposition date: 2014-08-29, release date: 2014-10-29, Last modification date: 2024-11-06) |
| Primary citation | Bischoff, L.,Berninghausen, O.,Beckmann, R. Molecular Basis for the Ribosome Functioning as an L-Tryptophan Sensor. Cell Rep., 9:469-, 2014 Cited by PubMed Abstract: Elevated levels of the free amino acid L-tryptophan (L-Trp) trigger expression of the tryptophanase tnaCAB operon in E. coli. Activation depends on tryptophan-dependent ribosomal stalling during translation of the upstream TnaC peptide. Here, we present a cryoelectron microscopy (cryo-EM) reconstruction at 3.8 Å resolution of a ribosome stalled by the TnaC peptide. Unexpectedly, we observe two L-Trp molecules in the ribosomal exit tunnel coordinated within composite hydrophobic pockets formed by the nascent TnaC peptide and the tunnel wall. As a result, the peptidyl transferase center (PTC) adopts a distinct conformation that precludes productive accommodation of release factor 2 (RF2), thereby inducing translational stalling. Collectively, our results demonstrate how the translating ribosome can act as a small molecule sensor for gene regulation. PubMed: 25310980DOI: 10.1016/J.CELREP.2014.09.011 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.8 Å) |
Structure validation
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