4CQN

Crystal structure of the E.coli LeuRS-tRNA complex with the non- cognate isoleucyl adenylate analogue

4CQN の概要

• エントリーDOI: 10.2210/pdb4cqn/pdb
• 分子名称: LEUCINE--TRNA LIGASE, ESCHERICHIA COLI TRNA-LEU UAA ISOACCEPTOR, ZINC ION, ... (6 entities in total)
• 機能のキーワード: ligase-rna complex, ligase, translational fidelity, adaptive response and evolution, ligase/rna
• 由来する生物種: ESCHERICHIA COLI K-12; 詳細
• 細胞内の位置: Cytoplasm: P07813
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 253996.92

構造登録者

Palencia, A.,Cusack, S.,Cvetesic, N.,Haslaz, I.,Gruic-Sovulj, I. (登録日: 2014-02-20, 公開日: 2014-07-02, 最終更新日: 2023-12-20)

主引用文献

Cvetesic, N.,Palencia, A.,Halasz, I.,Cusack, S.,Gruic-Sovulj, I.
The Physiological Target for Leurs Translational Quality Control is Norvaline
Embo J., 33:1639-, 2014

PubMed Abstract: The fidelity of protein synthesis depends on the capacity of aminoacyl-tRNA synthetases (AARSs) to couple only cognate amino acid-tRNA pairs. If amino acid selectivity is compromised, fidelity can be ensured by an inherent AARS editing activity that hydrolyses mischarged tRNAs. Here, we show that the editing activity of Escherichia coli leucyl-tRNA synthetase (EcLeuRS) is not required to prevent incorrect isoleucine incorporation. Rather, as shown by kinetic, structural and in vivo approaches, the prime biological function of LeuRS editing is to prevent mis-incorporation of the non-standard amino acid norvaline. This conclusion follows from a reassessment of the discriminatory power of LeuRS against isoleucine and the demonstration that a LeuRS editing-deficient E. coli strain grows normally in high concentrations of isoleucine but not under oxygen deprivation conditions when norvaline accumulates to substantial levels. Thus, AARS-based translational quality control is a key feature for bacterial adaptive response to oxygen deprivation. The non-essential role for editing under normal bacterial growth has important implications for the development of resistance to antimicrobial agents targeting the LeuRS editing site.

PubMed: 24935946
DOI: 10.15252/EMBJ.201488199

実験手法

X-RAY DIFFRACTION (2.5 Å)