View source for 4jz8


==Carbamate kinase from Giardia lamblia bound to citric acid==
<StructureSection load='4jz8' size='340' side='right'caption='[[4jz8]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4jz8]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Giardia_lamblia_ATCC_50803 Giardia lamblia ATCC 50803]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4JZ8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4JZ8 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CIT:CITRIC+ACID'>CIT</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=4jz8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4jz8 OCA], [https://pdbe.org/4jz8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4jz8 RCSB], [https://www.ebi.ac.uk/pdbsum/4jz8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4jz8 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A8BB85_GIAIC A8BB85_GIAIC] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The parasite Giardia lamblia utilizes the L-arginine dihydrolase pathway to generate ATP from L-arginine. Carbamate kinase (CK) catalyzes the last step in this pathway, converting ADP and carbamoyl phosphate to ATP and ammonium carbamate. Because the L-arginine pathway is essential for G. lamblia survival and absent in high eukaryotes including humans, the enzyme is a potential target for drug development. We have determined two crystal structures of G. lamblia CK (glCK) with bound ligands. One structure, in complex with a nonhydrolyzable ATP analog, adenosine 5'-adenylyl-beta,gamma-imidodiphosphate (AMP-PNP), was determined at 2.6 A resolution. The second structure, in complex with citric acid bound in the postulated carbamoyl phosphate binding site, was determined in two slightly different states at 2.1 and 2.4 A resolution. These structures reveal conformational flexibility of an auxiliary domain (amino acid residues 123-170), which exhibits open or closed conformations or structural disorder, depending on the bound ligand. The structures also reveal a smaller conformational change in a region associated the AMP-PNP adenine binding site. The protein residues involved in binding, together with a model of the transition state, suggest that catalysis follows an in-line, predominantly dissociative, phosphotransfer reaction mechanism, and that closure of the flexible auxiliary domain is required to protect the transition state from bulk solvent.

Crystal Structures of Carbamate Kinase from Giardia lamblia Bound with Citric Acid and AMP-PNP.,Lim K, Kulakova L, Galkin A, Herzberg O PLoS One. 2013 May 20;8(5):e64004. doi: 10.1371/journal.pone.0064004. Print 2013. PMID:23700444<ref>PMID:23700444</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4jz8" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Giardia lamblia ATCC 50803]]
[[Category: Large Structures]]
[[Category: Herzberg O]]
[[Category: Lim K]]