Ferredoxin/ferredoxin–thioredoxin reductase complex: Complete NMR mapping of the interaction site on ferredoxin by gallium substitution

• Published in: FEBS letters 2006-12, Vol.580 (28), p.6714-6720
• Main Authors: Xu, Xingfu, Kim, Sung-Kun, Schürmann, Peter, Hirasawa, Masakazu, Tripathy, Jatindra N., Smith, Jody, Knaff, David B., Ubbink, Marcellus
• Format: Article
• Language: English
• Subjects: [2Fe–2S] Ferredoxin; Amino Acid Sequence; Binding Sites; Chemical shift perturbation; Cyanobacteria; ferredoxin; Ferredoxins - chemistry; Ferredoxins - metabolism; ferredoxin–NADP reductase; Ferredoxin–thioredoxin reductase; FNR; FTR; GaFd; Gallium - metabolism; gallium substituted Fd; glutamate synthase; GOGAT; heteronuclear single-quantum correlation; HSQC; Iron-Sulfur Proteins - chemistry; Iron-Sulfur Proteins - metabolism; Models, Molecular; Molecular Sequence Data; NaR; NiR; nitrate reductase; nitrite reductase; NOESY; Nuclear Magnetic Resonance, Biomolecular - methods; nuclear Overhauser enhancement spectroscopy; Oxidoreductases - chemistry; Oxidoreductases - metabolism; SiR; sulfite reductase; Synechocystis; Synechocystis - enzymology; Titrimetry; TOCSY; total correlation spectroscopy
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/j.febslet.2006.11.027

The reduction of ferredoxin–thioredoxin reductase (FTR) by plant-type ferredoxin plays an important role in redox regulation in plants and cyanobacteria. Nuclear magnetic resonance (NMR) was used to map the binding sites on Synechocystis ferredoxin for FTR. A gallium-substituted structural analog of this [2Fe–2S] ferredoxin was obtained by reconstituting the apoprotein in a refolding buffer containing gallium. For the first time, the complete interaction interface of a [2Fe–2S] ferredoxin with a target enzyme has been mapped by NMR chemical shift perturbation with this diamagnetic structural analog.