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2p2g

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Revision as of 02:07, 11 September 2015

Crystal Structure of Ornithine Carbamoyltransferase from Mycobacterium Tuberculosis (Rv1656): Orthorhombic Form

Structural highlights

2p2g is a 6 chain structure with sequence from Myctu. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Gene:	argF, Rv1656, MT1694 (MYCTU)
Activity:	Ornithine carbamoyltransferase, with EC number 2.1.3.3
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, TOPSAN

Function

[OTC_MYCTU] Reversibly catalyzes the transfer of the carbamoyl group from carbamoyl phosphate (CP) to the N(epsilon) atom of ornithine (ORN) to produce L-citrulline, which is a substrate for argininosuccinate synthetase, the enzyme involved in the final step in arginine biosynthesis (By similarity).[HAMAP-Rule:MF_01109]

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

Mycobacterium tuberculosis ornithine carbamoyltransferase (Mtb OTC) catalyzes the sixth step in arginine biosynthesis; it produces citrulline from carbamoyl phosphate (CP) and ornithine (ORN). Here, we report the crystal structures of Mtb OTC in orthorhombic (form I) and hexagonal (form II) space groups. The molecules in form II are complexed with CP and l-norvaline (NVA); the latter is a competitive inhibitor of OTC. The asymmetric unit in form I contains a pseudo hexamer with 32 point group symmetry. The CP and NVA in form II induce a remarkable conformational change in the 80s and the 240s loops with the displacement of these loops towards the active site. The displacement of these loops is strikingly different from that seen in other OTC structures. In addition, the ligands induce a domain closure of 4.4 degrees in form II. Sequence comparison of active-site residues of Mtb OTC with several other OTCs of known structure reveals that they are virtually identical. The interactions involving the active-site residues of Mtb OTC with CP and NVA and a modeling study of ORN in the form II structure strongly rule out an earlier proposed mechanistic role of Cys264 in catalysis and suggest a possible mechanism for OTC. Our results strongly support the view that ORN with an already deprotonated N(epsilon) atom is the species that binds to the enzyme and that one of the phosphate oxygen atoms of CP is likely to be involved in accepting a proton from the doubly protonated N(epsilon) atom of ORN. We have interpreted this deprotonation as part of the collapse of the transition state of the reaction.

The crystal structures of ornithine carbamoyltransferase from Mycobacterium tuberculosis and its ternary complex with carbamoyl phosphate and L-norvaline reveal the enzyme's catalytic mechanism.,Sankaranarayanan R, Cherney MM, Cherney LT, Garen CR, Moradian F, James MN J Mol Biol. 2008 Jan 25;375(4):1052-63. Epub 2007 Nov 19. PMID:18062991^[1]

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

References

↑ Sankaranarayanan R, Cherney MM, Cherney LT, Garen CR, Moradian F, James MN. The crystal structures of ornithine carbamoyltransferase from Mycobacterium tuberculosis and its ternary complex with carbamoyl phosphate and L-norvaline reveal the enzyme's catalytic mechanism. J Mol Biol. 2008 Jan 25;375(4):1052-63. Epub 2007 Nov 19. PMID:18062991 doi:10.1016/j.jmb.2007.11.025

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2p2g"

@@ Line 2: / Line 2: @@
 <StructureSection load='2p2g' size='340' side='right' caption='[[2p2g]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[2p2g]] is a 6 chain structure with sequence from [http://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2P2G OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2P2G FirstGlance]. <br>
+<table><tr><td colspan='2'>[[2p2g]] is a 6 chain structure with sequence from [http://en.wikipedia.org/wiki/Myctu Myctu]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2P2G OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2P2G FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
-<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">argF, Rv1656, MT1694 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1773 Mycobacterium tuberculosis])</td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">argF, Rv1656, MT1694 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83332 MYCTU])</td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Ornithine_carbamoyltransferase Ornithine carbamoyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.3.3 2.1.3.3] </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=2p2g FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2p2g OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2p2g RCSB], [http://www.ebi.ac.uk/pdbsum/2p2g PDBsum], [http://www.topsan.org/Proteins/TBSGC/2p2g TOPSAN]</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=2p2g FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2p2g OCA], [http://pdbe.org/2p2g PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2p2g RCSB], [http://www.ebi.ac.uk/pdbsum/2p2g PDBsum], [http://www.topsan.org/Proteins/TBSGC/2p2g TOPSAN]</span></td></tr>
 </table>
 == Function ==
@@ Line 28: / Line 28: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 2p2g" style="background-color:#fffaf0;"></div>
 ==See Also==
@@ Line 35: / Line 36: @@
 __TOC__
 </StructureSection>
-[[Category: Mycobacterium tuberculosis]]
+[[Category: Myctu]]
 [[Category: Ornithine carbamoyltransferase]]
 [[Category: Cherney, L T]]
@@ Line 44: / Line 45: @@
 [[Category: Sankaranarayanan, R]]
 [[Category: Structural genomic]]
+[[Category: Mycobacterium tuberculosis]]
 [[Category: Ornithine carbamyoltransferase]]
 [[Category: PSI, Protein structure initiative]]
 [[Category: Tbsgc]]
 [[Category: Transferase]]

2p2g

From Proteopedia

Revision as of 02:07, 11 September 2015

Crystal Structure of Ornithine Carbamoyltransferase from Mycobacterium Tuberculosis (Rv1656): Orthorhombic Form

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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