1u8r
From Proteopedia
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| - | [[Image:1u8r.gif|left|200px]] | ||
| - | + | ==Crystal Structure of an IdeR-DNA Complex Reveals a Conformational Change in Activated IdeR for Base-specific Interactions== | |
| - | + | <StructureSection load='1u8r' size='340' side='right'caption='[[1u8r]], [[Resolution|resolution]] 2.75Å' scene=''> | |
| - | + | == Structural highlights == | |
| - | + | <table><tr><td colspan='2'>[[1u8r]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1U8R OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1U8R 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]] 2.75Å</td></tr> | |
| - | --> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CO:COBALT+(II)+ION'>CO</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=1u8r FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1u8r OCA], [https://pdbe.org/1u8r PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1u8r RCSB], [https://www.ebi.ac.uk/pdbsum/1u8r PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1u8r ProSAT]</span></td></tr> | |
| - | + | </table> | |
| - | + | == Function == | |
| - | + | [https://www.uniprot.org/uniprot/IDER_MYCTU IDER_MYCTU] Metal-dependent DNA-binding protein that controls transcription of many genes involved in iron metabolism. Acts as a repressor of siderophore biosynthesis and as a positive modulator of iron storage. Also regulates expression of transporters, proteins involved in siderophore synthesis, iron storage and transcriptional regulators.<ref>PMID:11722747</ref> <ref>PMID:12065475</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/u8/1u8r_consurf.spt"</scriptWhenChecked> | ||
| + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.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=1u8r ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
The iron-dependent regulator (IdeR) is an essential protein in Mycobacterium tuberculosis that regulates iron uptake in this major pathogen. Under high iron concentrations, IdeR binds to several operator regions and represses transcription of target genes. Here, we report the first crystal structure of cobalt-activated IdeR bound to the mbtA-mbtB operator at 2.75 A resolution. IdeR binds to the DNA as a "double-dimer" complex with two dimers on opposite sides of the DNA duplex with the dimer axes deviating approximately 157 degrees. The asymmetric unit contains two such double-dimer complexes with a total molecular mass of 240 kDa. Two metal-binding sites are fully occupied with the SH3-like third domain adopting a "wedge" position to interact with the two other domains, and providing two ligands for the metal site 1 in all eight subunits per asymmetric unit. A putative sodium ion is observed to mediate interactions between Asp35 and DNA. There is a conformational change in the DNA-binding domain caused by a 6-9 degrees rotation of the helix-turn-helix motif with respect to the rest of the molecule upon binding to the DNA. Ser37 and Pro39 make specific interactions with conserved thymine bases while Gln43 makes non-specific contacts with different types of bases in different subunits. A "p1s2C3T4a5" base recognition pattern is proposed to be the basis for key interactions for each IdeR subunit with the DNA in the IdeR-DNA complex structure. | The iron-dependent regulator (IdeR) is an essential protein in Mycobacterium tuberculosis that regulates iron uptake in this major pathogen. Under high iron concentrations, IdeR binds to several operator regions and represses transcription of target genes. Here, we report the first crystal structure of cobalt-activated IdeR bound to the mbtA-mbtB operator at 2.75 A resolution. IdeR binds to the DNA as a "double-dimer" complex with two dimers on opposite sides of the DNA duplex with the dimer axes deviating approximately 157 degrees. The asymmetric unit contains two such double-dimer complexes with a total molecular mass of 240 kDa. Two metal-binding sites are fully occupied with the SH3-like third domain adopting a "wedge" position to interact with the two other domains, and providing two ligands for the metal site 1 in all eight subunits per asymmetric unit. A putative sodium ion is observed to mediate interactions between Asp35 and DNA. There is a conformational change in the DNA-binding domain caused by a 6-9 degrees rotation of the helix-turn-helix motif with respect to the rest of the molecule upon binding to the DNA. Ser37 and Pro39 make specific interactions with conserved thymine bases while Gln43 makes non-specific contacts with different types of bases in different subunits. A "p1s2C3T4a5" base recognition pattern is proposed to be the basis for key interactions for each IdeR subunit with the DNA in the IdeR-DNA complex structure. | ||
| - | + | Crystal structure of an IdeR-DNA complex reveals a conformational change in activated IdeR for base-specific interactions.,Wisedchaisri G, Holmes RK, Hol WG J Mol Biol. 2004 Sep 24;342(4):1155-69. PMID:15351642<ref>PMID:15351642</ref> | |
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | <div class="pdbe-citations 1u8r" style="background-color:#fffaf0;"></div> | |
| - | + | == References == | |
| - | + | <references/> | |
| - | + | __TOC__ | |
| - | + | </StructureSection> | |
| - | [[Category: | + | [[Category: Large Structures]] |
| - | + | ||
| - | + | ||
[[Category: Mycobacterium tuberculosis]] | [[Category: Mycobacterium tuberculosis]] | ||
| - | [[Category: | + | [[Category: Hol WGJ]] |
| - | + | [[Category: Holmes RK]] | |
| + | [[Category: Wisedchaisri G]] | ||
Current revision
Crystal Structure of an IdeR-DNA Complex Reveals a Conformational Change in Activated IdeR for Base-specific Interactions
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