3fgs: Difference between revisions
New page: '''Unreleased structure''' The entry 3fgs is ON HOLD Authors: Halbrooks, Peter J., Mason, Anne B., Everse, Stephen J. Description: Crystal structure of G65R/K206E double mutant of the ... |
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==Crystal structure of G65R/K206E double mutant of the N-lobe human transferrin== | |||
<StructureSection load='3fgs' size='340' side='right'caption='[[3fgs]], [[Resolution|resolution]] 1.80Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[3fgs]] is a 1 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=3FGS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3FGS 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]] 1.8Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CO3:CARBONATE+ION'>CO3</scene>, <scene name='pdbligand=FE:FE+(III)+ION'>FE</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=3fgs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3fgs OCA], [https://pdbe.org/3fgs PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3fgs RCSB], [https://www.ebi.ac.uk/pdbsum/3fgs PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3fgs ProSAT]</span></td></tr> | |||
</table> | |||
== 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> | |||
== 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. | |||
== 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/fg/3fgs_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=3fgs ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The G65R mutation in the N-lobe of human transferrin was created to mimic a naturally occurring variant (G394R) found in the homologous C-lobe. Because Gly65 is hydrogen-bonded to the iron-binding ligand Asp63, it comprises part of the second-shell hydrogen bond network surrounding the iron within the metal-binding cleft of the protein. Substitution with an arginine residue at this position disrupts the network, resulting in much more facile removal of iron from the G65R mutant. As shown by UV-vis and EPR spectroscopy, and by kinetic assays measuring the release of iron, the G65R mutant can exist in three forms. Two of the forms (yellow and pink in color) are interconvertible. The yellow form predominates in 1 M bicarbonate; the pink form is generated from the yellow form upon exchange into 1 M HEPES buffer (pH 7.4). The third form (also pink in color) is produced by the addition of Fe(3+)-(nitrilotriacetate)(2) to apo-G65R. Hydrogen-deuterium exchange experiments are consistent with all forms of the G65R mutant assuming a more open conformation. Additionally, mass spectrometric analysis reveals the presence of nitrilotriacetate in the third form. The inability to obtain crystals of the G65R mutant led to development of a novel crystallization strategy in which the G65R/K206E double mutation stabilizes a single closed pink conformer and captures Arg65 in a single position. Collectively, these studies highlight the importance of the hydrogen bond network in the cleft, as well as the inherent flexibility of the N-lobe which, although able to adapt to accommodate the large arginine substitution, exists in multiple conformations. | |||
Structural and Functional Consequences of the Substitution of Glycine 65 with Arginine in the N-Lobe of Human Transferrin (dagger).,Mason AB, Halbrooks PJ, James NG, Byrne SL, Grady JK, Chasteen ND, Bobst CE, Kaltashov IA, Smith VC, Macgillivray RT, Everse SJ Biochemistry. 2009 Feb 16. PMID:19219998<ref>PMID:19219998</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 3fgs" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Transferrin 3D structures|Transferrin 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Homo sapiens]] | |||
[[Category: Large Structures]] | |||
[[Category: Everse SJ]] | |||
[[Category: Halbrooks PJ]] | |||
[[Category: Mason AB]] | |||