2akj

Structure of spinach nitrite reductase

spinqualitylabelsall models 2akj, resolution 2.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 2akj is a 1 chain structure with sequence from Spinacia oleracea. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.8Å Ligands: SRM Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function NIR_SPIOL Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed The structure of nitrite reductase, a key enzyme in the process of nitrogen assimilation, has been determined using X-ray diffraction to a resolution limit of 2.8 A. The protein has a globular fold consisting of 3 alpha/beta domains with the siroheme-iron sulfur cofactor at the interface of the three domains. The Fe(4)S(4) cluster is coordinated by cysteines 441, 447, 482, and 486. The siroheme is located at a distance of 4.2 A from the cluster, and the central iron atom is coordinated to Cys 486. The siroheme is surrounded by several ionizable amino acid residues that facilitate the binding and subsequent reduction of nitrite. A model for the ferredoxin:nitrite reductase complex is proposed in which the binding of ferredoxin to a positively charged region of nitrite reductase results in elimination of exposure of the cofactors to the solvent. The structure of nitrite reductase shows a broad similarity to the hemoprotein subunit of sulfite reductase but has many significant differences in the backbone positions that could reflect sequence differences or could arise from alterations of the sulfite reductase structure that arise from the isolation of this subunit from the native complex. The implications of the nitrite reductase structure for understanding multi-electron processes are discussed in terms of differences in the protein environments of the cofactors. Structure of spinach nitrite reductase: implications for multi-electron reactions by the iron-sulfur:siroheme cofactor.,Swamy U, Wang M, Tripathy JN, Kim SK, Hirasawa M, Knaff DB, Allen JP Biochemistry. 2005 Dec 13;44(49):16054-63. PMID:16331965 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Nitrite reductase 3D structures

Proteopedia Page Contributors and Editors (what is this?)

OCA