View source for 6oha


==Yeast Guanine Deaminase==
<StructureSection load='6oha' size='340' side='right'caption='[[6oha]], [[Resolution|resolution]] 2.21&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6oha]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae_S288C Saccharomyces cerevisiae S288C]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6OHA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6OHA 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]] 2.21&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1PE:PENTAETHYLENE+GLYCOL'>1PE</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=XAN:XANTHINE'>XAN</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=6oha FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6oha OCA], [https://pdbe.org/6oha PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6oha RCSB], [https://www.ebi.ac.uk/pdbsum/6oha PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6oha ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/GUAD_YEAST GUAD_YEAST] Catalyzes the hydrolytic deamination of guanine, producing xanthine and ammonia.<ref>PMID:15565584</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Guanine deaminase is a metabolic enzyme, found in all forms of life, which catalyzes the conversion of guanine to xanthine. Despite the availability of several crystal structures, the molecular determinants of substrate orientation and mechanism remain to be elucidated for the amidohydrolase family of guanine deaminase enzymes. Here, we report the crystal structures of Escherichia coli and Saccharomyces cerevisiae guanine deaminase enzymes (EcGuaD and Gud1, respectively), both members of the amidohydrolase superfamily. EcGuaD and Gud1 retain the overall TIM barrel tertiary structure conserved among amidohydrolase enzymes. Both proteins also possess a single zinc cation with trigonal bipyrimidal coordination geometry within their active sites. We also determined a liganded structure of Gud1 bound to the product, xanthine. Analysis of this structure, along with kinetic data of native and site-directed mutants of EcGuaD, identifies several key residues that are responsible for substrate recognition and catalysis. In addition, after a small library of compounds had been screened, two guanine derivatives, 8-azaguanine and 1-methylguanine, were identified as EcGuaD substrates. Interestingly, both EcGuaD and Gud1 also exhibit secondary ammeline deaminase activity. Overall, this work details key structural features of substrate recognition and catalysis of the amidohydrolase family of guanine deaminase enzymes in support of our long-term goal to engineer these enzymes with altered activity and substrate specificity.

Structural Determinants for Substrate Selectivity in Guanine Deaminase Enzymes of the Amidohydrolase Superfamily.,Shek R, Hilaire T, Sim J, French JB Biochemistry. 2019 Jul 19. doi: 10.1021/acs.biochem.9b00341. PMID:31283204<ref>PMID:31283204</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6oha" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae S288C]]
[[Category: French JB]]
[[Category: Shek RS]]