1FB0

CRYSTAL STRUCTURE OF THIOREDOXIN M FROM SPINACH CHLOROPLAST (REDUCED FORM)

1FB0 の概要

• エントリーDOI: 10.2210/pdb1fb0/pdb
• 関連するPDBエントリー: 1F9M 1FAA 1FB6
• 分子名称: THIOREDOXIN M (2 entities in total)
• 機能のキーワード: electron transport
• 由来する生物種: Spinacia oleracea (spinach)
• 細胞内の位置: Plastid, chloroplast: P07591
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 23586.87

構造登録者

Capitani, G.,Markovic-Housley, Z.,DelVal, G.,Morris, M.,Jansonius, J.N.,Schurmann, P. (登録日: 2000-07-14, 公開日: 2000-09-20, 最終更新日: 2024-02-07)

主引用文献

Capitani, G.,Markovic-Housley, Z.,DelVal, G.,Morris, M.,Jansonius, J.N.,Schurmann, P.
Crystal structures of two functionally different thioredoxins in spinach chloroplasts.
J.Mol.Biol., 302:135-154, 2000

PubMed Abstract: Thioredoxins are small ubiquitous proteins which act as general protein disulfide reductases in living cells. Chloroplasts contain two distinct thioredoxins ( f and m) with different phylogenetic origin. Both act as enzyme regulatory proteins but have different specificities towards target enzymes. Thioredoxin f (Trx f), which shares only low sequence identity with thioredoxin m (Trx m) and with all other known thioredoxins, activates enzymes of the Calvin cycle and other photosynthetic processes. Trx m shows high sequence similarity with bacterial thioredoxins and activates other chloroplast enzymes. The here described structural studies of the two chloroplast thioredoxins were carried out in order to gain insight into the structure/function relationships of these proteins. Crystal structures were determined for oxidized, recombinant thioredoxin f (Trx f-L) and at the N terminus truncated form of it (Trx f-S), as well as for oxidized and reduced thioredoxin m (at 2.1 and 2.3 A resolution, respectively). Whereas thioredoxin f crystallized as a monomer, both truncated thioredoxin f and thioredoxin m crystallized as non-covalent dimers. The structures of thioredoxins f and m exhibit the typical thioredoxin fold consisting of a central twisted five-stranded beta-sheet surrounded by four alpha-helices. Thioredoxin f contains an additional alpha-helix at the N terminus and an exposed third cysteine close to the active site. The overall three-dimensional structures of the two chloroplast thioredoxins are quite similar. However, the two proteins have a significantly different surface topology and charge distribution around the active site. An interesting feature which might significantly contribute to the specificity of thioredoxin f is an inherent flexibility of its active site, which has expressed itself crystallographically in two different crystal forms.

PubMed: 10964566
DOI: 10.1006/jmbi.2000.4006

実験手法

X-RAY DIFFRACTION (2.26 Å)