3E3K

Structural characterization of a putative endogenous metal chelator in the periplasmic nickel transporter NikA (butane-1,2,4-tricarboxylate without nickel form)

3E3K の概要

• エントリーDOI: 10.2210/pdb3e3k/pdb
• 関連するPDBエントリー: 1UIU 1UIV 1ZLQ 2NOO 3DP8
• 分子名称: Nickel-binding periplasmic protein, GLYCEROL, ACETATE ION, ... (7 entities in total)
• 機能のキーワード: nickel, nickellophore, butane-1, 2, 4-tricarboxylate, transport, metal transport
• 由来する生物種: Escherichia coli
• 細胞内の位置: Periplasm (Probable): P33590
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 170521.08

構造登録者

Cherrier, M.V.,Cavazza, C.,Bochot, C.,Lemaire, D.,Fontecilla-Camps, J.C. (登録日: 2008-08-07, 公開日: 2008-09-16, 最終更新日: 2023-11-01)

主引用文献

Cherrier, M.V.,Cavazza, C.,Bochot, C.,Lemaire, D.,Fontecilla-Camps, J.C.
Structural characterization of a putative endogenous metal chelator in the periplasmic nickel transporter NikA
Biochemistry, 47:9937-9943, 2008

PubMed Abstract: Escherichia coli and related bacteria require nickel for the synthesis of hydrogenases, enzymes involved in hydrogen oxidation and proton reduction. Nickel transport to the cytoplasm depends on five proteins, NikA-E. We have previously reported the three-dimensional structure of the soluble periplasmic nickel transporter NikA in a complex with FeEDTA(H 2O) (-). We have now determined the structure of EDTA-free NikA and have found that it binds a small organic molecule that contributes three ligands to the coordination of a transition metal ion. Unexpectedly, His416, which was far from the metal-binding site in the FeEDTA(H 2O) (-)-NikA complex, becomes the fourth observed ligand to the metal. The best match to the omit map electron density is obtained for butane-1,2,4-tricarboxylate (BTC). Our attempts to obtain a BTC-Ni-NikA complex using apo protein and commercial reagents resulted in nickel-free BTC-NikA. Overall, our results suggest that nickel transport in vivo requires a specific metallophore that may be BTC.

PubMed: 18759453
DOI: 10.1021/bi801051y

実験手法

X-RAY DIFFRACTION (2.8 Å)