3ajq | pdb_00003ajq
Crystal structure of human H ferritin E140Q mutant
Structural highlights
Function[FRIH_HUMAN] Stores iron in a soluble, non-toxic, readily available form. Important for iron homeostasis. Has ferroxidase activity. Iron is taken up in the ferrous form and deposited as ferric hydroxides after oxidation. Also plays a role in delivery of iron to cells. Mediates iron uptake in capsule cells of the developing kidney (By similarity). 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 PubMedFerritins are ubiquitous iron storage proteins. Recently, we identified a novel metal-binding site, transit site, in the crystal structure of phytoferritin. To elucidate the function of the transit site in ferritin from other species, we prepared transit-site-deficient mutants of human H ferritin, E140A and E140Q, and their iron oxidation kinetics was analyzed. The initial velocities of iron oxidization were reduced in the variants, especially in E140Q. The crystal structure of E140Q showed that the side chain of the mutated Gln140 was fixed by a hydrogen bond, whereas that of native Glu140 was flexible. These results suggest that the conserved transit site also has a function to assist with the metal ion sequestration to the ferroxidase site in ferritins from vertebrates. The universal mechanism for iron translocation to the ferroxidase site in ferritin, which is mediated by the well conserved transit site.,Masuda T, Goto F, Yoshihara T, Mikami B Biochem Biophys Res Commun. 2010 Aug 10. PMID:20705053[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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