1p3w: Difference between revisions

From Proteopedia
Jump to navigationJump to search
OCA (talk | contribs)
Bots, Bureaucrats, journal, Administrators
3,331,613 edits
New page: left|200px<br /><applet load="1p3w" size="450" color="white" frame="true" align="right" spinBox="true" caption="1p3w, resolution 2.1Å" /> '''X-ray crystal structu...
 
OCA (talk | contribs)
Bots, Bureaucrats, journal, Administrators
3,331,613 edits
No edit summary
 
(15 intermediate revisions by the same user not shown)
Line 1: Line 1:
[[Image:1p3w.gif|left|200px]]<br /><applet load="1p3w" size="450" color="white" frame="true" align="right" spinBox="true"
caption="1p3w, resolution 2.1&Aring;" />
'''X-ray crystal structure of E. coli IscS'''<br />


==Overview==
==X-ray crystal structure of E. coli IscS==
IscS is a widely distributed cysteine desulfurase that catalyzes the, pyridoxal phosphate-dependent desulfuration of L-cysteine and plays a, central role in the delivery of sulfur to a variety of metabolic pathways., We report the crystal structure of Escherichia coli IscS to a resolution, of 2.1A. The crystals belong to the space group P2(1)2(1)2(1) and have, unit cell dimensions a=73.70A, b=101.97A, c=108.62A (alpha=beta=gamma=90, degrees ). Molecular replacement with the Thermotoga maritima NifS model, was used to determine phasing, and the IscS model was refined to an, R=20.6% (R(free)=23.6%) with two molecules per asymmetric unit. The, structure of E.coli IscS is similar to that of T.maritima NifS with nearly, identical secondary structure and an overall backbone r.m.s. difference of, 1.4A. However, in contrast to NifS a peptide segment containing the, catalytic cysteine residue (Cys328) is partially ordered in the IscS, structure. This segment of IscS (residues 323-335) forms a surface loop, directed away from the active site pocket. Cys328 is positioned greater, than 17A from the pyridoxal phosphate cofactor, suggesting that a large, conformational change must occur during catalysis in order for Cys328 to, participate in nucleophilic attack of a pyridoxal phosphate-bound cysteine, substrate. Modeling suggests that rotation of this loop may allow movement, of Cys328 to within approximately 3A of the pyridoxal phosphate cofactor.
<StructureSection load='1p3w' size='340' side='right'caption='[[1p3w]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1p3w]] 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=1P3W OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1P3W 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</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=1p3w FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1p3w OCA], [https://pdbe.org/1p3w PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1p3w RCSB], [https://www.ebi.ac.uk/pdbsum/1p3w PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1p3w ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ISCS_ECOLI ISCS_ECOLI] Master enzyme that delivers sulfur to a number of partners involved in Fe-S cluster assembly, tRNA modification or cofactor biosynthesis. Catalyzes the removal of elemental sulfur from cysteine to produce alanine. Functions as a sulfur delivery protein for Fe-S cluster synthesis onto IscU, an Fe-S scaffold assembly protein, as well as other S acceptor proteins. Preferentially binds to disordered IscU on which the Fe-S is assembled, IscU converts to the structured state and then dissociates from IscS to transfer the Fe-S to an acceptor protein. Also functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Transfers sulfur onto 'Cys-456' of ThiI and onto 'Cys-19' of TusA in transpersulfidation reactions.<ref>PMID:8663056</ref> <ref>PMID:10829016</ref> <ref>PMID:11577100</ref> <ref>PMID:16387657</ref> <ref>PMID:22203963</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/p3/1p3w_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=1p3w ConSurf].
<div style="clear:both"></div>


==About this Structure==
==See Also==
1P3W is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with PLP as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1P3W OCA].
*[[Cysteine desulfurase 3D structures|Cysteine desulfurase 3D structures]]
 
== References ==
==Reference==
<references/>
Crystal structure of IscS, a cysteine desulfurase from Escherichia coli., Cupp-Vickery JR, Urbina H, Vickery LE, J Mol Biol. 2003 Jul 25;330(5):1049-59. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=12860127 12860127]
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Escherichia coli]]
[[Category: Single protein]]
[[Category: Large Structures]]
[[Category: Cupp-Vickery, J.R.]]
[[Category: Cupp-Vickery JR]]
[[Category: Urbina, H.]]
[[Category: Urbina H]]
[[Category: Vickery, L.E.]]
[[Category: Vickery LE]]
[[Category: PLP]]
[[Category: csdb]]
[[Category: iron sulfur cluster]]
[[Category: nifs]]
 
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 23:27:18 2007''
Retrieved from "https://proteopedia.org/1p3w"