View source for 6vi7


==Probing extradiol dioxygenase mechanism in NAD(+) biosynthesis by viewing reaction cycle intermediates - a substrate bidentately bound structure==
<StructureSection load='6vi7' size='340' side='right'caption='[[6vi7]], [[Resolution|resolution]] 2.62&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6vi7]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Cupriavidus_metallidurans_CH34 Cupriavidus metallidurans CH34]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6VI7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6VI7 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]] 2.617&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=3HA:3-HYDROXYANTHRANILIC+ACID'>3HA</scene>, <scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene>, <scene name='pdbligand=TRS:2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>TRS</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=6vi7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6vi7 OCA], [https://pdbe.org/6vi7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6vi7 RCSB], [https://www.ebi.ac.uk/pdbsum/6vi7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6vi7 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/3HAO_CUPMC 3HAO_CUPMC] Catalyzes the oxidative ring opening of 3-hydroxyanthranilate to 2-amino-3-carboxymuconate semialdehyde, which spontaneously cyclizes to quinolinate.[HAMAP-Rule:MF_00825]<ref>PMID:15909977</ref> 
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== Publication Abstract from PubMed ==
The synthesis of quinolinic acid from tryptophan is a critical step in the de novo biosynthesis of nicotinamide adenine dinucleotide (NAD(+)) in mammals. Herein, the nonheme iron-based 3-hydroxyanthranilate-3,4-dioxygenase responsible for quinolinic acid production was studied by performing time-resolved in crystallo reactions monitored by UV-vis microspectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and X-ray crystallography. Seven catalytic intermediates were kinetically and structurally resolved in the crystalline state, and each accompanies protein conformational changes at the active site. Among them, a monooxygenated, seven-membered lactone intermediate as a monodentate ligand of the iron center at 1.59-A resolution was captured, which presumably corresponds to a substrate-based radical species observed by EPR using a slurry of small-sized single crystals. Other structural snapshots determined at around 2.0-A resolution include monodentate and subsequently bidentate coordinated substrate, superoxo, alkylperoxo, and two metal-bound enol tautomers of the unstable dioxygenase product. These results reveal a detailed stepwise O-atom transfer dioxygenase mechanism along with potential isomerization activity that fine-tunes product profiling and affects the production of quinolinic acid at a junction of the metabolic pathway.

Observing 3-hydroxyanthranilate-3,4-dioxygenase in action through a crystalline lens.,Wang Y, Liu KF, Yang Y, Davis I, Liu A Proc Natl Acad Sci U S A. 2020 Jul 30. pii: 2005327117. doi:, 10.1073/pnas.2005327117. PMID:32732435<ref>PMID:32732435</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 6vi7" style="background-color:#fffaf0;"></div>

==See Also==
*[[Dioxygenase 3D structures|Dioxygenase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Cupriavidus metallidurans CH34]]
[[Category: Large Structures]]
[[Category: Liu A]]
[[Category: Liu F]]
[[Category: Wang Y]]
[[Category: Yang Y]]