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From Proteopedia
THE X-RAY STRUCTURE OF THE UNUSUAL DODECAMERIC FERRITIN FROM LISTERIA INNOCUA, REVEALS A NOVEL INTERSUBUNIT IRON BINDING SITE.
Structural highlights
FunctionDPS_LISIN Protects DNA from oxidative damage by sequestering intracellular Fe(2+) ion and storing it in the form of Fe(3+) oxyhydroxide mineral. One hydrogen peroxide oxidizes two Fe(2+) ions, which prevents hydroxyl radical production by the Fenton reaction. Does not bind DNA.[1] [2] [3] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedFerritin is characterized by a highly conserved architecture that comprises 24 subunits assembled into a spherical cage with 432 symmetry. The only known exception is the dodecameric ferritin from Listeria innocua. The structure of Listeria ferritin has been determined to a resolution of 2.35 A by molecular replacement, using as a search model the structure of Dps from Escherichia coli. The Listeria 12-mer is endowed with 23 symmetry and displays the functionally relevant structural features of the ferritin 24-mer, namely the negatively charged channels along the three-fold symmetry axes that serve for iron entry into the cavity and a negatively charged internal cavity for iron deposition. The electron density map shows 12 iron ions on the inner surface of the hollow core, at the interface between monomers related by two-fold axes. Analysis of the nature and stereochemistry of the iron-binding ligands reveals strong similarities with known ferroxidase sites. The L. innocua ferritin site, however, is the first described so far that has ligands belonging to two different subunits and is not contained within a four-helix bundle. The dodecameric ferritin from Listeria innocua contains a novel intersubunit iron-binding site.,Ilari A, Stefanini S, Chiancone E, Tsernoglou D Nat Struct Biol. 2000 Jan;7(1):38-43. PMID:10625425[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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