6SPP

Structure of the Escherichia coli methionyl-tRNA synthetase variant VI298

6SPP の概要

• エントリーDOI: 10.2210/pdb6spp/pdb
• 関連するPDBエントリー: 1QQT
• 分子名称: Methionine--tRNA ligase, ZINC ION, CITRIC ACID, ... (5 entities in total)
• 機能のキーワード: trna aminoacylation, translation
• 由来する生物種: Escherichia coli
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 65285.78

構造登録者

Nigro, G.,Schmitt, E.,Mechulam, Y. (登録日: 2019-09-02, 公開日: 2020-01-01, 最終更新日: 2024-01-24)

主引用文献

Nigro, G.,Bourcier, S.,Lazennec-Schurdevin, C.,Schmitt, E.,Marliere, P.,Mechulam, Y.
Use of beta3-methionine as an amino acid substrate of Escherichia coli methionyl-tRNA synthetase.
J.Struct.Biol., 209:107435-107435, 2020

PubMed Abstract: Polypeptides containing β-amino acids are attractive tools for the design of novel proteins having unique properties of medical or industrial interest. Incorporation of β-amino acids in vivo requires the development of efficient aminoacyl-tRNA synthetases specific of these non-canonical amino acids. Here, we have performed a detailed structural and biochemical study of the recognition and use of β-Met by Escherichia coli methionyl-tRNA synthetase (MetRS). We show that MetRS binds β-Met with a 24-fold lower affinity but catalyzes the esterification of the non-canonical amino acid onto tRNA with a rate lowered by three orders of magnitude. Accurate measurements of the catalytic parameters required careful consideration of the presence of contaminating α-Met in β-Met commercial samples. The 1.45 Å crystal structure of the MetRS: β-Met complex shows that β-Met binds the enzyme essentially like α-Met, but the carboxylate moiety is mobile and not adequately positioned to react with ATP for aminoacyl adenylate formation. This study provides structural and biochemical bases for engineering MetRS with improved β-Met aminoacylation capabilities.

PubMed: 31862305
DOI: 10.1016/j.jsb.2019.107435

実験手法

X-RAY DIFFRACTION (1.49 Å)