5X6B

Crystal structure of SepCysE-SepCysS in complex with tRNACys from Methanocaldococcus jannaschii

5X6B の概要

• エントリーDOI: 10.2210/pdb5x6b/pdb
• 関連するPDBエントリー: 5X6C
• 分子名称: O-phospho-L-seryl-tRNA:Cys-tRNA synthase, Uncharacterized protein MJ1481, tRNACys, ... (4 entities in total)
• 機能のキーワード: sepcyse, multidomain protein, rna binding protein-rna complex, rna binding protein/rna
• 由来する生物種: Methanocaldococcus jannaschii DSM 2661; 詳細
• タンパク質・核酸の鎖数: 5
• 化学式量合計: 169875.78

構造登録者

Chen, M.,Kato, K.,Yao, M. (登録日: 2017-02-21, 公開日: 2017-12-06, 最終更新日: 2023-11-22)

主引用文献

Chen, M.,Kato, K.,Kubo, Y.,Tanaka, Y.,Liu, Y.,Long, F.,Whitman, W.B.,Lill, P.,Gatsogiannis, C.,Raunser, S.,Shimizu, N.,Shinoda, A.,Nakamura, A.,Tanaka, I.,Yao, M.
Structural basis for tRNA-dependent cysteine biosynthesis
Nat Commun, 8:1521-1521, 2017

PubMed Abstract: Cysteine can be synthesized by tRNA-dependent mechanism using a two-step indirect pathway, where O-phosphoseryl-tRNA synthetase (SepRS) catalyzes the ligation of a mismatching O-phosphoserine (Sep) to tRNA followed by the conversion of tRNA-bounded Sep into cysteine by Sep-tRNA:Cys-tRNA synthase (SepCysS). In ancestral methanogens, a third protein SepCysE forms a bridge between the two enzymes to create a ternary complex named the transsulfursome. By combination of X-ray crystallography, SAXS and EM, together with biochemical evidences, here we show that the three domains of SepCysE each bind SepRS, SepCysS, and tRNA, respectively, which mediates the dynamic architecture of the transsulfursome and thus enables a global long-range channeling of tRNA between SepRS and SepCysS distant active sites. This channeling mechanism could facilitate the consecutive reactions of the two-step indirect pathway of Cys-tRNA synthesis (tRNA-dependent cysteine biosynthesis) to prevent challenge of translational fidelity, and may reflect the mechanism that cysteine was originally added into genetic code.

PubMed: 29142195
DOI: 10.1038/s41467-017-01543-y

実験手法

X-RAY DIFFRACTION (2.596 Å)