3e1n: Difference between revisions
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< | ==Crystal structure of E. coli Bacterioferritin (BFR) after a 65 minute (aerobic) exposure to FE(II) revealing a possible MU-OXO bridge/MU-Hydroxy bridged DIIRON intermediate at the ferroxidase centre. (FE(III)-O-FE(III)-BFR).== | ||
<StructureSection load='3e1n' size='340' side='right'caption='[[3e1n]], [[Resolution|resolution]] 2.80Å' scene=''> | |||
You may | == Structural highlights == | ||
or the | <table><tr><td colspan='2'>[[3e1n]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3E1N OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3E1N FirstGlance]. <br> | ||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.8Å</td></tr> | |||
- | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | ||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=3e1n FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3e1n OCA], [https://pdbe.org/3e1n PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3e1n RCSB], [https://www.ebi.ac.uk/pdbsum/3e1n PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3e1n ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/BFR_ECOLI BFR_ECOLI] Iron-storage protein, whose ferroxidase center binds Fe(2+) ions, oxidizes them by dioxygen to Fe(3+), and participates in the subsequent Fe(3+) oxide mineral core formation within the central cavity of the protein complex. The mineralized iron core can contain as many as 2700 iron atoms/24-meric molecule.<ref>PMID:10769150</ref> <ref>PMID:14636073</ref> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/e1/3e1n_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=3e1n ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Ferritin proteins function to detoxify, solubilize and store cellular iron by directing the synthesis of a ferric oxyhydroxide mineral solubilized within the protein's central cavity. Here, through the application of X-ray crystallographic and kinetic methods, we report significant new insight into the mechanism of mineralization in a bacterioferritin (BFR). The structures of nonheme iron-free and di-Fe(2+) forms of BFR showed that the intrasubunit catalytic center, known as the ferroxidase center, is preformed, ready to accept Fe(2+) ions with little or no reorganization. Oxidation of the di-Fe(2+) center resulted in a di-Fe(3+) center, with bridging electron density consistent with a mu-oxo or hydro bridged species. The mu-oxo bridged di-Fe(3+) center appears to be stable, and there is no evidence that Fe(3+)species are transferred into the core from the ferroxidase center. Most significantly, the data also revealed a novel Fe(2+) binding site on the inner surface of the protein, lying approximately 10 A directly below the ferroxidase center, coordinated by only two residues, His46 and Asp50. Kinetic studies of variants containing substitutions of these residues showed that the site is functionally important. In combination, the data support a model in which the ferroxidase center functions as a true catalytic cofactor, rather than as a pore for the transfer of iron into the central cavity, as found for eukaryotic ferritins. The inner surface iron site appears to be important for the transfer of electrons, derived from Fe(2+) oxidation in the cavity, to the ferroxidase center. Bacterioferritin may represent an evolutionary link between ferritins and class II di-iron proteins not involved in iron metabolism. | |||
Structural basis for iron mineralization by bacterioferritin.,Crow A, Lawson TL, Lewin A, Moore GR, Le Brun NE J Am Chem Soc. 2009 May 20;131(19):6808-13. PMID:19391621<ref>PMID:19391621</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 3e1n" style="background-color:#fffaf0;"></div> | |||
== | ==See Also== | ||
*[[Ferritin 3D structures|Ferritin 3D structures]] | |||
[[Category: Escherichia coli]] | == References == | ||
[[Category: | <references/> | ||
[[Category: Crow | __TOC__ | ||
[[Category: Lawson | </StructureSection> | ||
[[Category: | [[Category: Escherichia coli K-12]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: | [[Category: Crow A]] | ||
[[Category: Lawson T]] | |||
[[Category: Le Brun N]] | |||
[[Category: Lewin A]] | |||
[[Category: Moore GR]] | |||
Latest revision as of 09:30, 12 February 2025
Crystal structure of E. coli Bacterioferritin (BFR) after a 65 minute (aerobic) exposure to FE(II) revealing a possible MU-OXO bridge/MU-Hydroxy bridged DIIRON intermediate at the ferroxidase centre. (FE(III)-O-FE(III)-BFR).Crystal structure of E. coli Bacterioferritin (BFR) after a 65 minute (aerobic) exposure to FE(II) revealing a possible MU-OXO bridge/MU-Hydroxy bridged DIIRON intermediate at the ferroxidase centre. (FE(III)-O-FE(III)-BFR).
Structural highlights
FunctionBFR_ECOLI Iron-storage protein, whose ferroxidase center binds Fe(2+) ions, oxidizes them by dioxygen to Fe(3+), and participates in the subsequent Fe(3+) oxide mineral core formation within the central cavity of the protein complex. The mineralized iron core can contain as many as 2700 iron atoms/24-meric molecule.[1] [2] 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 PubMedFerritin proteins function to detoxify, solubilize and store cellular iron by directing the synthesis of a ferric oxyhydroxide mineral solubilized within the protein's central cavity. Here, through the application of X-ray crystallographic and kinetic methods, we report significant new insight into the mechanism of mineralization in a bacterioferritin (BFR). The structures of nonheme iron-free and di-Fe(2+) forms of BFR showed that the intrasubunit catalytic center, known as the ferroxidase center, is preformed, ready to accept Fe(2+) ions with little or no reorganization. Oxidation of the di-Fe(2+) center resulted in a di-Fe(3+) center, with bridging electron density consistent with a mu-oxo or hydro bridged species. The mu-oxo bridged di-Fe(3+) center appears to be stable, and there is no evidence that Fe(3+)species are transferred into the core from the ferroxidase center. Most significantly, the data also revealed a novel Fe(2+) binding site on the inner surface of the protein, lying approximately 10 A directly below the ferroxidase center, coordinated by only two residues, His46 and Asp50. Kinetic studies of variants containing substitutions of these residues showed that the site is functionally important. In combination, the data support a model in which the ferroxidase center functions as a true catalytic cofactor, rather than as a pore for the transfer of iron into the central cavity, as found for eukaryotic ferritins. The inner surface iron site appears to be important for the transfer of electrons, derived from Fe(2+) oxidation in the cavity, to the ferroxidase center. Bacterioferritin may represent an evolutionary link between ferritins and class II di-iron proteins not involved in iron metabolism. Structural basis for iron mineralization by bacterioferritin.,Crow A, Lawson TL, Lewin A, Moore GR, Le Brun NE J Am Chem Soc. 2009 May 20;131(19):6808-13. PMID:19391621[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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