3M9J

Crystal structure of human thioredoxin C69/73S double mutant, reduced form

3M9J の概要

• エントリーDOI: 10.2210/pdb3m9j/pdb
• 関連するPDBエントリー: 1ERT
• 分子名称: Thioredoxin (2 entities in total)
• 機能のキーワード: oxidoreductase
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Nucleus : P10599
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 23436.70

構造登録者

Weichsel, A.,Montfort, W.R. (登録日: 2010-03-22, 公開日: 2010-08-11, 最終更新日: 2023-09-06)

主引用文献

Weichsel, A.,Kem, M.,Montfort, W.R.
Crystal structure of human thioredoxin revealing an unraveled helix and exposed S-nitrosation site.
Protein Sci., 19:1801-1806, 2010

PubMed Abstract: Thioredoxins reduce disulfide bonds and other thiol modifications in all cells using a CXXC motif. Human thioredoxin 1 is unusual in that it codes for an additional three cysteines in its 105 amino acid sequence, each of which have been implicated in other reductive activities. Cys 62 and Cys 69 are buried in the protein interior and lie at either end of a short helix (helix 3), and yet can disulfide link under oxidizing conditions. Cys 62 is readily S-nitrosated, giving rise to a SNO modification, which is also buried. Here, we present two crystal structures of the C69S/C73S mutant protein under oxidizing (1.5 A) and reducing (1.1 A) conditions. In the oxidized structure, helix 3 is unraveled and displays a new conformation that is stabilized by a series of new hydrogen bonds and a disulfide link with Cys 62 in a neighboring molecule. The new conformation provides an explanation for how a completely buried residue can participate in SNO exchange reactions.

PubMed: 20662007
DOI: 10.1002/pro.455

実験手法

X-RAY DIFFRACTION (1.1 Å)