7O1C

Cryo-EM structure of an Escherichia coli TnaC(R23F)-ribosome-RF2 complex stalled in response to L-tryptophan

これはPDB形式変換不可エントリーです。

7O1C の概要

• エントリーDOI: 10.2210/pdb7o1c/pdb
• 関連するPDBエントリー: 7O19 7O1A
• EMDBエントリー: 12695
• 分子名称: Ribosomal RNA 16S, 30S ribosomal protein S10, 30S ribosomal protein S11, ... (61 entities in total)
• 機能のキーワード: ribosome, regulation, tnac, arrest peptide, l-tryptophan, translation, indole, stalling
• 由来する生物種: Escherichia coli K-12; 詳細
• タンパク質・核酸の鎖数: 56
• 化学式量合計: 2221664.70

構造登録者

van der Stel, A.X.,Gordon, E.R.,Sengupta, A.,Martinez, A.K.,Klepacki, D.,Perry, T.N.,Herrero del Valle, A.,Vazquez-Laslop, N.,Sachs, M.S.,Cruz-Vera, L.R.,Innis, C.A. (登録日: 2021-03-29, 公開日: 2021-09-01, 最終更新日: 2025-03-19)

主引用文献

van der Stel, A.X.,Gordon, E.R.,Sengupta, A.,Martinez, A.K.,Klepacki, D.,Perry, T.N.,Herrero Del Valle, A.,Vazquez-Laslop, N.,Sachs, M.S.,Cruz-Vera, L.R.,Innis, C.A.
Structural basis for the tryptophan sensitivity of TnaC-mediated ribosome stalling.
Nat Commun, 12:5340-5340, 2021

PubMed Abstract: Free L-tryptophan (L-Trp) stalls ribosomes engaged in the synthesis of TnaC, a leader peptide controlling the expression of the Escherichia coli tryptophanase operon. Despite extensive characterization, the molecular mechanism underlying the recognition and response to L-Trp by the TnaC-ribosome complex remains unknown. Here, we use a combined biochemical and structural approach to characterize a TnaC variant (R23F) with greatly enhanced sensitivity for L-Trp. We show that the TnaC-ribosome complex captures a single L-Trp molecule to undergo termination arrest and that nascent TnaC prevents the catalytic GGQ loop of release factor 2 from adopting an active conformation at the peptidyl transferase center. Importantly, the L-Trp binding site is not altered by the R23F mutation, suggesting that the relative rates of L-Trp binding and peptidyl-tRNA cleavage determine the tryptophan sensitivity of each variant. Thus, our study reveals a strategy whereby a nascent peptide assists the ribosome in detecting a small metabolite.

PubMed: 34504068
DOI: 10.1038/s41467-021-25663-8

実験手法

ELECTRON MICROSCOPY (2.6 Å)