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1amj

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Revision as of 10:44, 8 November 2017

STERIC AND CONFORMATIONAL FEATURES OF THE ACONITASE MECHANISM

Structural highlights

1amj is a 1 chain structure with sequence from Bovin. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, ,
Activity:	Aconitate hydratase, with EC number 4.2.1.3
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[ACON_BOVIN] Catalyzes the isomerization of citrate to isocitrate via cis-aconitate.

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

Crystal structures of mitochondrial aconitase with alpha-methylisocitrate and with sulfate bound have been solved and refined at 2.0 A resolution with R factors of 18.2 and 16.8%, respectively. The steric factors and conformational effects observed in both new structures support the proposed mechanism for the overall reaction catalyzed by aconitase. The alternate substrate alpha-methylisocitrate is derived from alpha-methyl-cis-aconitate during crystallization and is observed to bind in the active site in a manner very similar to that observed for isocitrate. The methyl group is accommodated by favorable contact with Ile-425. However, the other potential hydration product of alpha-methyl-cis-aconitate, alpha-methylcitrate, cannot be accommodated in the active site due to steric conflict of the methyl group with Asp-165. The results are consistent with the requirement that cis-aconitate must bind in two ways, in the citrate mode and in the isocitrate mode. Crystals of aconitase with sulfate bound are isomorphous to those with isocitrate bound. However, the structure displays significant conformational changes, providing a model for the substrate-free state of enzyme. Three water molecules bind in place of the C alpha- and C beta-hydroxyl and carboxyl groups of isocitrate, while sulfate binds in place of the C gamma-carboxyl group. Side chains of Ser-642 and Arg-447 in the active site rotate to pair with other side chains in the absence of substrate. The new conformation of Arg-447 triggers a concerted set of shifts which transmits conformational change to the surface of the protein, 30 A from the active site. In the absence of substrate, a chain segment containing the [4Fe-4S] ligand Cys-358 also shifts, resulting in the net translation and reorientation of the Fe-S cluster.

Steric and conformational features of the aconitase mechanism.,Lauble H, Stout CD Proteins. 1995 May;22(1):1-11. PMID:7675781^[1]

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

References

↑ Lauble H, Stout CD. Steric and conformational features of the aconitase mechanism. Proteins. 1995 May;22(1):1-11. PMID:7675781 doi:http://dx.doi.org/10.1002/prot.340220102

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/1amj"

Categories: Aconitate hydratase | Bovin | Stout, C D

@@ Line 1: / Line 1: @@
 ==STERIC AND CONFORMATIONAL FEATURES OF THE ACONITASE MECHANISM==
 <StructureSection load='1amj' size='340' side='right' caption='[[1amj]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
@@ Line 5: / Line 6: @@
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=OH:HYDROXIDE+ION'>OH</scene>, <scene name='pdbligand=SF4:IRON/SULFUR+CLUSTER'>SF4</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Aconitate_hydratase Aconitate hydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.3 4.2.1.3] </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=1amj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1amj OCA], [http://pdbe.org/1amj PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1amj RCSB], [http://www.ebi.ac.uk/pdbsum/1amj 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=1amj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1amj OCA], [http://pdbe.org/1amj PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1amj RCSB], [http://www.ebi.ac.uk/pdbsum/1amj PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1amj ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 28: / Line 29: @@
 </div>
 <div class="pdbe-citations 1amj" style="background-color:#fffaf0;"></div>
-==See Also==
-*[[Aconitase|Aconitase]]
 == References ==
 <references/>

1amj

From Proteopedia

Revision as of 10:44, 8 November 2017

STERIC AND CONFORMATIONAL FEATURES OF THE ACONITASE MECHANISM

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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