View source for 2z29


==Thr109Ala dihydroorotase from E. coli==
<StructureSection load='2z29' size='340' side='right'caption='[[2z29]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2z29]] 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=2Z29 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2Z29 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]] 1.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=DOR:(4S)-2,6-DIOXOHEXAHYDROPYRIMIDINE-4-CARBOXYLIC+ACID'>DOR</scene>, <scene name='pdbligand=KCX:LYSINE+NZ-CARBOXYLIC+ACID'>KCX</scene>, <scene name='pdbligand=NCD:N-CARBAMOYL-L-ASPARTATE'>NCD</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=2z29 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2z29 OCA], [https://pdbe.org/2z29 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2z29 RCSB], [https://www.ebi.ac.uk/pdbsum/2z29 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2z29 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PYRC_ECOLI PYRC_ECOLI] 
== 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/z2/2z29_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=2z29 ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Dihydroorotase (DHOase) catalyzes the reversible cyclization of N-carbamyl-l-aspartate (CA-asp) to l-dihydroorotate (DHO) in the de novo biosynthesis of pyrimidine nucleotides. Two different conformations of the surface loop (residues 105-115) were found in the dimeric Escherichia coli DHOase crystallized in the presence of DHO (PDB code 1XGE). The loop asymmetry reflected that of the active site contents of the two subunits: the product, DHO, was bound in the active site of one subunit and the substrate, CA-asp, in the active site of the other. In the substrate- (CA-asp-) bound subunit, the surface loop reaches in toward the active site and makes hydrogen bonds with the bound CA-asp via two threonine residues (Thr109 and Thr110), whereas the loop forms part of the surface of the protein in the product- (DHO-) bound subunit. To investigate the relationship between the structural states of this loop and the catalytic mechanism of the enzyme, a series of mutant DHOases including deletion of the flexible loop were generated and characterized kinetically and structurally. Disruption of the hydrogen bonds between the surface loop and the substrate results in significant loss of catalytic activity. Furthermore, structures of these mutants with low catalytic activity have no interpretable electron density for parts of the flexible loop. The structure of the mutant (Delta107-116), in which the flexible loop is deleted, shows only small differences in positions of other substrate binding residues and in the binuclear zinc center compared with the native structure, yet the enzyme has negligible activity. The kinetic and structural analyses suggest that Thr109 and Thr110 in the flexible loop provide productive binding of substrate and stabilize the transition-state intermediate, thereby increasing catalytic activity.

Kinetic and structural analysis of mutant Escherichia coli dihydroorotases: a flexible loop stabilizes the transition state.,Lee M, Maher MJ, Christopherson RI, Guss JM Biochemistry. 2007 Sep 18;46(37):10538-50. Epub 2007 Aug 21. PMID:17711307<ref>PMID:17711307</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2z29" style="background-color:#fffaf0;"></div>

==See Also==
*[[Dihydroorotase 3D structures|Dihydroorotase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Guss JM]]
[[Category: Lee M]]
[[Category: Maher MJ]]