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4hf0
From Proteopedia
(Difference between revisions)
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== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[4hf0]] is a 2 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=4HF0 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4HF0 FirstGlance]. <br> | <table><tr><td colspan='2'>[[4hf0]] is a 2 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=4HF0 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4HF0 FirstGlance]. <br> | ||
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></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]] 1.9Å</td></tr> |
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><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=4hf0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4hf0 OCA], [https://pdbe.org/4hf0 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4hf0 RCSB], [https://www.ebi.ac.uk/pdbsum/4hf0 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4hf0 ProSAT]</span></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=4hf0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4hf0 OCA], [https://pdbe.org/4hf0 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4hf0 RCSB], [https://www.ebi.ac.uk/pdbsum/4hf0 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4hf0 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[https://www.uniprot.org/uniprot/ISCR_ECOLI ISCR_ECOLI] Regulates the transcription of several operons and genes involved in the biogenesis of Fe-S clusters and Fe-S-containing proteins. Transcriptional repressor of the iscRSUA operon, which is involved in the assembly of Fe-S clusters into Fe-S proteins. In its apoform, under conditions of oxidative stress or iron deprivation, it activates the suf operon, which is a second operon involved in the assembly of Fe-S clusters. Represses its own transcription as well as that of toxin rnlA.<ref>PMID:11742080</ref> <ref>PMID:16824106</ref> <ref>PMID:20421606</ref> | [https://www.uniprot.org/uniprot/ISCR_ECOLI ISCR_ECOLI] Regulates the transcription of several operons and genes involved in the biogenesis of Fe-S clusters and Fe-S-containing proteins. Transcriptional repressor of the iscRSUA operon, which is involved in the assembly of Fe-S clusters into Fe-S proteins. In its apoform, under conditions of oxidative stress or iron deprivation, it activates the suf operon, which is a second operon involved in the assembly of Fe-S clusters. Represses its own transcription as well as that of toxin rnlA.<ref>PMID:11742080</ref> <ref>PMID:16824106</ref> <ref>PMID:20421606</ref> | ||
| - | <div style="background-color:#fffaf0;"> | ||
| - | == Publication Abstract from PubMed == | ||
| - | IscR from Escherichia coli is an unusual metalloregulator in that both apo and iron sulfur (Fe-S)-IscR regulate transcription and exhibit different DNA binding specificities. Here, we report structural and biochemical studies of IscR suggesting that remodeling of the protein-DNA interface upon Fe-S ligation broadens the DNA binding specificity of IscR from binding the type 2 motif only to both type 1 and type 2 motifs. Analysis of an apo-IscR variant with relaxed target-site discrimination identified a key residue in wild-type apo-IscR that, we propose, makes unfavorable interactions with a type 1 motif. Upon Fe-S binding, these interactions are apparently removed, thereby allowing holo-IscR to bind both type 1 and type 2 motifs. These data suggest a unique mechanism of ligand-mediated DNA site recognition, whereby metallocluster ligation relocates a protein-specificity determinant to expand DNA target-site selection, allowing a broader transcriptomic response by holo-IscR. | ||
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| - | Studies of IscR reveal a unique mechanism for metal-dependent regulation of DNA binding specificity.,Rajagopalan S, Teter SJ, Zwart PH, Brennan RG, Phillips KJ, Kiley PJ Nat Struct Mol Biol. 2013 Jun;20(6):740-7. doi: 10.1038/nsmb.2568. Epub 2013 May , 5. PMID:23644595<ref>PMID:23644595</ref> | ||
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| - | </div> | ||
| - | <div class="pdbe-citations 4hf0" style="background-color:#fffaf0;"></div> | ||
== References == | == References == | ||
<references/> | <references/> | ||
Current revision
Crystal Structure of Apo IscR
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