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| | <StructureSection load='1bp5' size='340' side='right'caption='[[1bp5]], [[Resolution|resolution]] 2.20Å' scene=''> | | <StructureSection load='1bp5' size='340' side='right'caption='[[1bp5]], [[Resolution|resolution]] 2.20Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[1bp5]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BP5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1BP5 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[1bp5]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BP5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1BP5 FirstGlance]. <br> |
| - | </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=1bp5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1bp5 OCA], [https://pdbe.org/1bp5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1bp5 RCSB], [https://www.ebi.ac.uk/pdbsum/1bp5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1bp5 ProSAT]</span></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.2Å</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=1bp5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1bp5 OCA], [https://pdbe.org/1bp5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1bp5 RCSB], [https://www.ebi.ac.uk/pdbsum/1bp5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1bp5 ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Disease == | | == Disease == |
| - | [[https://www.uniprot.org/uniprot/TRFE_HUMAN TRFE_HUMAN]] Defects in TF are the cause of atransferrinemia (ATRAF) [MIM:[https://omim.org/entry/209300 209300]]. Atransferrinemia is rare autosomal recessive disorder characterized by iron overload and hypochromic anemia.<ref>PMID:11110675</ref> <ref>PMID:15466165</ref>
| + | [https://www.uniprot.org/uniprot/TRFE_HUMAN TRFE_HUMAN] Defects in TF are the cause of atransferrinemia (ATRAF) [MIM:[https://omim.org/entry/209300 209300]. Atransferrinemia is rare autosomal recessive disorder characterized by iron overload and hypochromic anemia.<ref>PMID:11110675</ref> <ref>PMID:15466165</ref> |
| | == Function == | | == Function == |
| - | [[https://www.uniprot.org/uniprot/TRFE_HUMAN TRFE_HUMAN]] Transferrins are iron binding transport proteins which can bind two Fe(3+) ions in association with the binding of an anion, usually bicarbonate. It is responsible for the transport of iron from sites of absorption and heme degradation to those of storage and utilization. Serum transferrin may also have a further role in stimulating cell proliferation.
| + | [https://www.uniprot.org/uniprot/TRFE_HUMAN TRFE_HUMAN] Transferrins are iron binding transport proteins which can bind two Fe(3+) ions in association with the binding of an anion, usually bicarbonate. It is responsible for the transport of iron from sites of absorption and heme degradation to those of storage and utilization. Serum transferrin may also have a further role in stimulating cell proliferation. |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Human]] | + | [[Category: Homo sapiens]] |
| | [[Category: Large Structures]] | | [[Category: Large Structures]] |
| - | [[Category: Baker, E N]] | + | [[Category: Baker EN]] |
| - | [[Category: Bewley, M C]] | + | [[Category: Bewley MC]] |
| - | [[Category: Jeffrey, P D]] | + | [[Category: Jeffrey PD]] |
| - | [[Category: Macgillivray, R T.A]] | + | [[Category: Macgillivray RTA]] |
| - | [[Category: Mason, A B]] | + | [[Category: Mason AB]] |
| - | [[Category: Woodworth, R C]] | + | [[Category: Woodworth RC]] |
| - | [[Category: Carbonate]]
| + | |
| - | [[Category: Glycoprotein]]
| + | |
| - | [[Category: Iron transport]]
| + | |
| - | [[Category: Iron-release]]
| + | |
| - | [[Category: Metal transport]]
| + | |
| - | [[Category: Nlobe]]
| + | |
| - | [[Category: Transferrin]]
| + | |
| Structural highlights
Disease
TRFE_HUMAN Defects in TF are the cause of atransferrinemia (ATRAF) [MIM:209300. Atransferrinemia is rare autosomal recessive disorder characterized by iron overload and hypochromic anemia.[1] [2]
Function
TRFE_HUMAN Transferrins are iron binding transport proteins which can bind two Fe(3+) ions in association with the binding of an anion, usually bicarbonate. It is responsible for the transport of iron from sites of absorption and heme degradation to those of storage and utilization. Serum transferrin may also have a further role in stimulating cell proliferation.
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
Serum transferrin binds ferric ions in the bloodstream and transports them to cells, where they are released in a process involving receptor-mediated endocytosis. Iron release is believed to be pH dependent and is coupled with a large conformational change. To help define the steps in iron release, we have determined the three-dimensional structure of the iron-free (apo) form of the recombinant N-lobe half-molecule of human serum transferrin (ApoTfN) by X-ray crystallography. Two crystal forms were obtained, form 1 with four molecules in the asymmetric unit and form 2 with two molecules in the asymmetric unit. The structures of both forms were determined by molecular replacement and were refined at 2.2 and 3.2 A resolution, respectively. Final R-factors were 0.203 (free R = 0. 292) for form 1 and 0.217 (free R = 0.312) for form 2. All six copies of the ApoTfN structure are essentially identical. Comparison with the holo form (FeTfN) shows that a large rigid-body domain movement of 63 degrees has occurred in ApoTfN, to give an open binding cleft. The extent of domain opening is the same as in the N-lobe of human lactoferrin, showing that it depends on internal constraints that are conserved in both proteins, and that it is unaffected by the presence or absence of the C-lobe. Although the conformational change is primarily a rigid-body motion, several local adjustments occur. In particular, two iron ligands, Asp 63 and His 249, change conformation to form salt bridges, with Lys 296 and Glu 83, respectively, in the binding cleft of the apo protein. Both salt bridges would have to break for iron coordination to occur. Most importantly, the structure, determined at a pH (5.3) that is close to the pH of physiological iron release, indicates that protonation of His 249 is a key step in iron release.
Ligand-induced conformational change in transferrins: crystal structure of the open form of the N-terminal half-molecule of human transferrin.,Jeffrey PD, Bewley MC, MacGillivray RT, Mason AB, Woodworth RC, Baker EN Biochemistry. 1998 Oct 6;37(40):13978-86. PMID:9760232[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Beutler E, Gelbart T, Lee P, Trevino R, Fernandez MA, Fairbanks VF. Molecular characterization of a case of atransferrinemia. Blood. 2000 Dec 15;96(13):4071-4. PMID:11110675
- ↑ Knisely AS, Gelbart T, Beutler E. Molecular characterization of a third case of human atransferrinemia. Blood. 2004 Oct 15;104(8):2607. PMID:15466165 doi:10.1182/blood-2004-05-1751
- ↑ Jeffrey PD, Bewley MC, MacGillivray RT, Mason AB, Woodworth RC, Baker EN. Ligand-induced conformational change in transferrins: crystal structure of the open form of the N-terminal half-molecule of human transferrin. Biochemistry. 1998 Oct 6;37(40):13978-86. PMID:9760232 doi:10.1021/bi9812064
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