1i9d: Difference between revisions

From Proteopedia
Jump to navigation Jump to search
← Older edit
No edit summary
No edit summary
 
(13 intermediate revisions by the same user not shown)
Line 1: Line 1:
[[Image:1i9d.jpg|left|200px]]<br /><applet load="1i9d" size="350" color="white" frame="true" align="right" spinBox="true"
caption="1i9d, resolution 1.65&Aring;" />
'''ARSENATE REDUCTASE FROM E. COLI'''<br />


==Overview==
==ARSENATE REDUCTASE FROM E. COLI==
BACKGROUND: In Escherichia coli bearing the plasmid R773, resistance to arsenite, arsenate, antimonite, and tellurite is conferred by the arsRDABC plasmid operon that codes for an ATP-dependent anion pump. The product of the arsC gene, arsenate reductase (ArsC), is required to efficiently catalyze the reduction of arsenate to arsenite prior to extrusion. RESULTS: Here, we report the first X-ray crystal structures of ArsC at 1.65 A and of ArsC complexed with arsenate and arsenite at 1.26 A resolution. The overall fold is unique. The native structure shows sulfate and sulfite ions binding in the active site as analogs of arsenate and arsenite. The covalent adduct of arsenate with Cys-12 in the active site of ArsC, which was analyzed in a difference map, shows tetrahedral geometry with a sulfur-arsenic distance of 2.18 A. However, the corresponding adduct with arsenite binds as a hitherto unseen thiarsahydroxy adduct. Finally, the number of bound waters (385) in this highly ordered crystal structure approaches twice the number expected at this resolution for a structure of 138 ordered residues. CONCLUSIONS: Structural information from the adduct of ArsC with its substrate (arsenate) and with its product (arsenite) together with functional information from mutational and biochemical studies on ArsC suggest a plausible mechanism for the reaction. The exceptionally well-defined water structure indicates that this crystal system has precise long-range order within the crystal and that the upper limit for the number of bound waters in crystal structures is underestimated by the structures in the Protein Data Bank.
<StructureSection load='1i9d' size='340' side='right'caption='[[1i9d]], [[Resolution|resolution]] 1.65&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1i9d]] is a 1 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=1I9D OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1I9D 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]] 1.65&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CS:CESIUM+ION'>CS</scene>, <scene name='pdbligand=SO3:SULFITE+ION'>SO3</scene>, <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=1i9d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i9d OCA], [https://pdbe.org/1i9d PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1i9d RCSB], [https://www.ebi.ac.uk/pdbsum/1i9d PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1i9d ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ARSC1_ECOLX ARSC1_ECOLX] Reduction of arsenate [As(V)] to arsenite [As(III)]. This protein expands the substrate specificity of ArsAB pump which can extrude arsenite and antimonite to allow for arsenate pumping and resistance.
== 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/i9/1i9d_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=1i9d ConSurf].
<div style="clear:both"></div>


==About this Structure==
==See Also==
1I9D 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 <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=SO3:'>SO3</scene> and <scene name='pdbligand=CS:'>CS</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1I9D OCA].
*[[Arsenate reductase 3D structures|Arsenate reductase 3D structures]]
 
__TOC__
==Reference==
</StructureSection>
Insights into the structure, solvation, and mechanism of ArsC arsenate reductase, a novel arsenic detoxification enzyme., Martin P, DeMel S, Shi J, Gladysheva T, Gatti DL, Rosen BP, Edwards BF, Structure. 2001 Nov;9(11):1071-81. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=11709171 11709171]
[[Category: Escherichia coli]]
[[Category: Escherichia coli]]
[[Category: Single protein]]
[[Category: Large Structures]]
[[Category: Edwards, B F.]]
[[Category: Edwards BF]]
[[Category: Martin, P.]]
[[Category: Martin P]]
[[Category: CS]]
[[Category: SO3]]
[[Category: SO4]]
[[Category: arsenate]]
[[Category: arsenic]]
[[Category: reductase]]
 
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:09:26 2008''

Latest revision as of 10:33, 7 February 2024

ARSENATE REDUCTASE FROM E. COLIARSENATE REDUCTASE FROM E. COLI

Structural highlights

1i9d is a 1 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 1.65Å
Ligands:, ,
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

ARSC1_ECOLX Reduction of arsenate [As(V)] to arsenite [As(III)]. This protein expands the substrate specificity of ArsAB pump which can extrude arsenite and antimonite to allow for arsenate pumping and resistance.

Evolutionary Conservation

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

See Also

1i9d, resolution 1.65Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA
Retrieved from "https://proteopedia.openfox.io/wiki/index.php?title=1i9d&oldid=4044824"