1s98
From Proteopedia
(Difference between revisions)
(One intermediate revision not shown.) | |||
Line 3: | Line 3: | ||
<StructureSection load='1s98' size='340' side='right'caption='[[1s98]], [[Resolution|resolution]] 2.30Å' scene=''> | <StructureSection load='1s98' size='340' side='right'caption='[[1s98]], [[Resolution|resolution]] 2.30Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
- | <table><tr><td colspan='2'>[[1s98]] is a 2 chain structure with sequence from [ | + | <table><tr><td colspan='2'>[[1s98]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1S98 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1S98 FirstGlance]. <br> |
- | </td></tr><tr id=' | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.3Å</td></tr> |
- | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1s98 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1s98 OCA], [https://pdbe.org/1s98 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1s98 RCSB], [https://www.ebi.ac.uk/pdbsum/1s98 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1s98 ProSAT]</span></td></tr> |
</table> | </table> | ||
== Function == | == Function == | ||
- | [ | + | [https://www.uniprot.org/uniprot/ISCA_ECOLI ISCA_ECOLI] Is able to transfer iron-sulfur clusters to apo-ferredoxin. Multiple cycles of [2Fe2S] cluster formation and transfer are observed, suggesting that IscA acts catalytically. Recruits intracellular free iron so as to provide iron for the assembly of transient iron-sulfur cluster in IscU in the presence of IscS, L-cysteine and the thioredoxin reductase system TrxA/TrxB.[HAMAP-Rule:MF_01429] |
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
Line 19: | Line 19: | ||
</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=1s98 ConSurf]. | </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=1s98 ConSurf]. | ||
<div style="clear:both"></div> | <div style="clear:both"></div> | ||
- | <div style="background-color:#fffaf0;"> | ||
- | == Publication Abstract from PubMed == | ||
- | IscA, an 11 kDa member of the hesB family of proteins, binds iron and [2Fe-2S] clusters, and participates in the biosynthesis of iron-sulfur proteins. We report the crystal structure of the apo-protein form of IscA from Escherichia coli to a resolution of 2.3A. The crystals belong to the space group P3(2)21 and have unit cell dimensions a=b=66.104 A, c=150.167 A (alpha=beta=90 degrees, gamma=120 degrees ). The structure was solved using single-wavelength anomalous dispersion (SAD) phasing of a selenomethionyl derivative, and the IscA model was refined to R=21.4% (Rfree=25.4%). IscA exists as an (alpha1alpha2)2 homotetramer with the (alpha1alpha2) dimer comprising the asymmetric unit. Cys35, implicated in Fe-S cluster assembly, is located in a central cavity formed at the tetramer interface with the gamma-sulfur atoms of residues from the alpha1 and alpha2' monomers (and alpha1'alpha2) positioned close to one another (approximately equal 7 A). C-terminal residues 99-107 are disordered, and the exact positions of Cys99 and Cys101 could not be determined. However, computer modeling of C-terminal residues in the tetramer suggests that Cys99 and Cys101 in the alpha1 monomer and those of the alpha1' monomer (or alpha2 and alpha2') are positioned sufficiently close to coordinate [2Fe-2S] clusters between the two dimers, whereas this is not possible within the (alpha1alpha2) or (alpha1'alpha2') dimer. This symmetrical arrangement allows for binding of two [2Fe-2S] clusters on opposite sides of the tetramer. Modeling further reveals that Cys101 is positioned sufficiently close to Cys35 to allow Cys35 to participate in cluster assembly, formation, or transfer. | ||
- | |||
- | Crystal structure of IscA, an iron-sulfur cluster assembly protein from Escherichia coli.,Cupp-Vickery JR, Silberg JJ, Ta DT, Vickery LE J Mol Biol. 2004 Apr 16;338(1):127-37. PMID:15050828<ref>PMID:15050828</ref> | ||
- | |||
- | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
- | </div> | ||
- | <div class="pdbe-citations 1s98" style="background-color:#fffaf0;"></div> | ||
- | == References == | ||
- | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
- | [[Category: | + | [[Category: Escherichia coli]] |
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
- | [[Category: Cupp-Vickery | + | [[Category: Cupp-Vickery JR]] |
- | [[Category: Silberg | + | [[Category: Silberg JJ]] |
- | [[Category: Ta | + | [[Category: Ta DT]] |
- | [[Category: Vickery | + | [[Category: Vickery LE]] |
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + |
Current revision
E.coli IscA crystal structure to 2.3 A
|