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1p3w

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Revision as of 12:37, 25 December 2014

X-ray crystal structure of E. coli IscS

Structural highlights

1p3w is a 2 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Gene:	ISCS OR B2530 OR C3056 OR Z3797 OR ECS3396 OR SF2577 (Escherichia coli)
Resources:	FirstGlance, OCA, RCSB, PDBsum

Function

[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.^[1] ^[2] ^[3] ^[4] ^[5]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

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.

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:12860127^[6]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Flint DH. Escherichia coli contains a protein that is homologous in function and N-terminal sequence to the protein encoded by the nifS gene of Azotobacter vinelandii and that can participate in the synthesis of the Fe-S cluster of dihydroxy-acid dehydratase. J Biol Chem. 1996 Jul 5;271(27):16068-74. PMID:8663056
↑ Lacourciere GM, Mihara H, Kurihara T, Esaki N, Stadtman TC. Escherichia coli NifS-like proteins provide selenium in the pathway for the biosynthesis of selenophosphate. J Biol Chem. 2000 Aug 4;275(31):23769-73. PMID:10829016 doi:10.1074/jbc.M000926200
↑ Urbina HD, Silberg JJ, Hoff KG, Vickery LE. Transfer of sulfur from IscS to IscU during Fe/S cluster assembly. J Biol Chem. 2001 Nov 30;276(48):44521-6. Epub 2001 Sep 27. PMID:11577100 doi:http://dx.doi.org/10.1074/jbc.M106907200
↑ Ikeuchi Y, Shigi N, Kato J, Nishimura A, Suzuki T. Mechanistic insights into sulfur relay by multiple sulfur mediators involved in thiouridine biosynthesis at tRNA wobble positions. Mol Cell. 2006 Jan 6;21(1):97-108. PMID:16387657 doi:http://dx.doi.org/S1097-2765(05)01761-2
↑ Kim JH, Tonelli M, Markley JL. Disordered form of the scaffold protein IscU is the substrate for iron-sulfur cluster assembly on cysteine desulfurase. Proc Natl Acad Sci U S A. 2012 Jan 10;109(2):454-9. doi: 10.1073/pnas.1114372109., Epub 2011 Dec 27. PMID:22203963 doi:http://dx.doi.org/10.1073/pnas.1114372109
↑ Cupp-Vickery JR, Urbina H, Vickery LE. Crystal structure of IscS, a cysteine desulfurase from Escherichia coli. J Mol Biol. 2003 Jul 25;330(5):1049-59. PMID:12860127

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1p3w"

@@ Line 3: / Line 3: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1p3w]] is a 2 chain structure with sequence from [http://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 [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1P3W FirstGlance]. <br>
-</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene><br>
+</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene></td></tr>
-<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">ISCS OR B2530 OR C3056 OR Z3797 OR ECS3396 OR SF2577 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli])</td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">ISCS OR B2530 OR C3056 OR Z3797 OR ECS3396 OR SF2577 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli])</td></tr>
-<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1p3w FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1p3w OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1p3w RCSB], [http://www.ebi.ac.uk/pdbsum/1p3w PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1p3w FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1p3w OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1p3w RCSB], [http://www.ebi.ac.uk/pdbsum/1p3w PDBsum]</span></td></tr>
-<table>
+</table>
+== Function ==
+[[http://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]]
@@ Line 30: / Line 32: @@
 </StructureSection>
 [[Category: Escherichia coli]]
-[[Category: Cupp-Vickery, J R.]]
+[[Category: Cupp-Vickery, J R]]
-[[Category: Urbina, H.]]
+[[Category: Urbina, H]]
-[[Category: Vickery, L E.]]
+[[Category: Vickery, L E]]
 [[Category: Csdb]]
 [[Category: Iron sulfur cluster]]
 [[Category: Lyase]]
 [[Category: Nif]]

1p3w

From Proteopedia

Revision as of 12:37, 25 December 2014

X-ray crystal structure of E. coli IscS

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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