View source for 3ox2


==X-ray Structural study of quinone reductase II inhibition by compounds with micromolar to nanomolar range IC50 values==
<StructureSection load='3ox2' size='340' side='right' caption='[[3ox2]], [[Resolution|resolution]] 2.41&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3ox2]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3OX2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3OX2 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=79X:2-HYDROXY-8,9-DIMETHOXY-6H-ISOINDOLO[2,1-A]INDOL-6-ONE'>79X</scene>, <scene name='pdbligand=FAD:FLAVIN-ADENINE+DINUCLEOTIDE'>FAD</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3owx|3owx]], [[3ovm|3ovm]], [[3owh|3owh]], [[3ox1|3ox1]]</td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">NQO2, NMOR2 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Ribosyldihydronicotinamide_dehydrogenase_(quinone) Ribosyldihydronicotinamide dehydrogenase (quinone)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.10.99.2 1.10.99.2] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3ox2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ox2 OCA], [http://pdbe.org/3ox2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3ox2 RCSB], [http://www.ebi.ac.uk/pdbsum/3ox2 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3ox2 ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/NQO2_HUMAN NQO2_HUMAN]] The enzyme apparently serves as a quinone reductase in connection with conjugation reactions of hydroquinones involved in detoxification pathways as well as in biosynthetic processes such as the vitamin K-dependent gamma-carboxylation of glutamate residues in prothrombin synthesis.<ref>PMID:18254726</ref>  
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Quinone reductase 2 (QR2) is one of two members comprising the mammalian quinone reductase family of enzymes responsible for performing FAD mediated reductions of quinone substrates. In contrast to quinone reductase 1 (QR1) which uses NAD(P)H as its co-substrate, QR2 utilizes a rare group of hydride donors, N-methyl or N-ribosyl nicotinamide. Several studies have linked QR2 to the generation of quinone free radicals, several neuronal degenerative diseases, and cancer. QR2 has been also identified as the third melatonin receptor (MT3) through in cellulo and in vitro inhibition of QR2 by traditional MT3 ligands, and through recent X-ray structures of human QR2 (hQR2) in complex with melatonin and 2-iodomelatonin. Several MT3 specific ligands have been developed that exhibit both potent in cellulo inhibition of hQR2 nanomolar, affinity for MT3. The potency of these ligands suggest their use as molecular probes for hQR2. However, no definitive correlation between traditionally obtained MT3 ligand affinity and hQR2 inhibition exists limiting our understanding of how these ligands are accommodated in the hQR2 active site. To obtain a clearer relationship between the structures of developed MT3 ligands and their inhibitory properties, in cellulo and in vitro IC(50) values were determined for a representative set of MT3 ligands (MCA-NAT, 2-I-MCANAT, prazosin, S26695, S32797, and S29434). Furthermore, X-ray structures for each of these ligands in complex with hQR2 were determined allowing for a structural evaluation of the binding modes of these ligands in relation to the potency of MT3 ligands.

X-ray structural studies of quinone reductase 2 nanomolar range inhibitors.,Pegan SD, Sturdy M, Ferry G, Delagrange P, Boutin JA, Mesecar AD Protein Sci. 2011 May 2. doi: 10.1002/pro.647. PMID:21538647<ref>PMID:21538647</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3ox2" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Human]]
[[Category: Mesecar, A D]]
[[Category: Pegan, S D]]
[[Category: Sturdy, M]]
[[Category: Fad]]
[[Category: Flavoprotein]]
[[Category: Metal-2 binding]]
[[Category: Nq02]]
[[Category: Oxidoreductase]]
[[Category: Phosphoprotein]]
[[Category: Qr2]]