1sda
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CRYSTAL STRUCTURE OF PEROXYNITRITE-MODIFIED BOVINE CU,ZN SUPEROXIDE DISMUTASE
OverviewOverview
The crystal structure of bovine Cu,Zn superoxide dismutase modified with peroxynitrite (ONOO-) was determined by X-ray diffraction, utilizing the existing three-dimensional model of the native structure deposited in the Brookhaven Protein Data Bank (J. A. Tainer et al., J. Mol. Biol. 160, 181-217, 1982). The native structure and the modified derivative were refined to R factors of 19.0 and 18.7% respectively using diffraction data from 6.0 to 2.5 A. The major result after reaction with peroxynitrite was the appearance of electron density 1.45 A from a single epsilon carbon of Tyr-108, the only tyrosine residue in the sequence. Tyr-108 is a solvent-exposed residue 18 A from the copper atom in the active site. The electron density was consistent with nitration of Tyr-108 at one of the epsilon carbons to form 3-nitrotyrosine. We propose that the nitration occurs in solution by transfer of a nitronium-like species from the active site on one superoxide dismutase dimer to the Tyr-108 of a second dimer.
About this StructureAbout this Structure
1SDA is a Single protein structure of sequence from Bos taurus with , , and as ligands. Active as Superoxide dismutase, with EC number 1.15.1.1 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of peroxynitrite-modified bovine Cu,Zn superoxide dismutase., Smith CD, Carson M, van der Woerd M, Chen J, Ischiropoulos H, Beckman JS, Arch Biochem Biophys. 1992 Dec;299(2):350-5. PMID:1444476
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