6c4k
From Proteopedia
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==Full length hUGDH with A104L substitution in the absence of ligand== | ==Full length hUGDH with A104L substitution in the absence of ligand== | ||
- | <StructureSection load='6c4k' size='340' side='right' caption='[[6c4k]], [[Resolution|resolution]] 2.65Å' scene=''> | + | <StructureSection load='6c4k' size='340' side='right'caption='[[6c4k]], [[Resolution|resolution]] 2.65Å' scene=''> |
== Structural highlights == | == Structural highlights == | ||
- | <table><tr><td colspan='2'>[[6c4k]] is a 3 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6C4K OCA]. For a <b>guided tour on the structure components</b> use [ | + | <table><tr><td colspan='2'>[[6c4k]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6C4K OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6C4K FirstGlance]. <br> |
- | </td></tr><tr id=' | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.65Å</td></tr> |
- | <tr id=' | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene></td></tr> |
- | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=6c4k FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6c4k OCA], [https://pdbe.org/6c4k PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6c4k RCSB], [https://www.ebi.ac.uk/pdbsum/6c4k PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6c4k ProSAT]</span></td></tr> |
</table> | </table> | ||
== Function == | == Function == | ||
- | [ | + | [https://www.uniprot.org/uniprot/UGDH_HUMAN UGDH_HUMAN] Involved in the biosynthesis of glycosaminoglycans; hyaluronan, chondroitin sulfate, and heparan sulfate. |
+ | <div style="background-color:#fffaf0;"> | ||
+ | == Publication Abstract from PubMed == | ||
+ | Human UDP-glucose dehydrogenase (hUGDH) oxidizes UDP-glucose to UDP-glucuronic acid, an essential substrate in the phase II metabolism of drugs. The activity of hUGDH is regulated by the conformation of a buried allosteric switch (T131-loop/alpha6 helix). Substrate binding induces the allosteric switch to slowly isomerize from an inactive E* conformation to the active E state, which can be observed as enzyme hysteresis. When the feedback inhibitor UDP-xylose binds, the allosteric switch and surrounding residues in the protein core repack, converting the hexamer into an inactive, horseshoe-shaped complex (E(Omega)). This allosteric transition is facilitated by large cavities and declivities in the protein core that provide the space required to accommodate the alternate packing arrangements. Here, we have used the A104L substitution to fill a cavity in the E state and sterically prevent repacking of the core into the E(Omega) state. Steady state analysis shows that hUGDHA104L binds UDP-xylose with lower affinity and that the inhibition is no longer cooperative. This means that the allosteric transition to the high UDP-xylose affinity E(Omega) state is blocked by the substitution. The crystal structures of hUGDHA104L show that the allosteric switch still adopts the E and E* states, albeit with a more rigid protein core. However, the progress curves of hUGDHA104L do not show hysteresis, which suggests that the E* and E states are now in rapid equilibrium. Our data suggests that hysteresis in native hUGDH originates from the conformational entropy of the E* state protein core. | ||
+ | |||
+ | Hysteresis and Allostery in Human UDP-Glucose Dehydrogenase Require a Flexible Protein Core.,Beattie NR, Pioso B, Sidlo AM, Keul ND, Wood ZA Biochemistry. 2018 Nov 20. doi: 10.1021/acs.biochem.8b00497. PMID:30457329<ref>PMID:30457329</ref> | ||
+ | |||
+ | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
+ | </div> | ||
+ | <div class="pdbe-citations 6c4k" style="background-color:#fffaf0;"></div> | ||
+ | == References == | ||
+ | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
- | [[Category: | + | [[Category: Homo sapiens]] |
- | [[Category: | + | [[Category: Large Structures]] |
- | [[Category: | + | [[Category: Beattie NR]] |
- | [[Category: | + | [[Category: Pioso BJ]] |
- | [[Category: | + | [[Category: Wood ZA]] |
- | + | ||
- | + |
Current revision
Full length hUGDH with A104L substitution in the absence of ligand
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