View source for 4nv5


==C50A mutant of Synechococcus VKOR, C2 crystal form (dehydrated)==
<StructureSection load='4nv5' size='340' side='right'caption='[[4nv5]], [[Resolution|resolution]] 2.79&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4nv5]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Synechococcus_sp._JA-2-3B'a(2-13) Synechococcus sp. JA-2-3B'a(2-13)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4NV5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4NV5 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]] 2.79&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=U10:UBIQUINONE-10'>U10</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=4nv5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4nv5 OCA], [https://pdbe.org/4nv5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4nv5 RCSB], [https://www.ebi.ac.uk/pdbsum/4nv5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4nv5 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/VKOR_SYNJB VKOR_SYNJB] Thiol-disulfide oxidoreductase that catalyzes vitamin K-dependent disulfide bond formation in periplasmic target proteins.<ref>PMID:20110994</ref> <ref>PMID:24477003</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The intramembrane vitamin K epoxide reductase (VKOR) supports blood coagulation in humans and is the target of the anticoagulant warfarin. VKOR and its homologues generate disulphide bonds in organisms ranging from bacteria to humans. Here, to better understand the mechanism of VKOR catalysis, we report two crystal structures of a bacterial VKOR captured in different reaction states. These structures reveal a short helix at the hydrophobic active site of VKOR that alters between wound and unwound conformations. Motions of this 'horizontal helix' promote electron transfer by regulating the positions of two cysteines in an adjacent loop. Winding of the helix separates these 'loop cysteines' to prevent backward electron flow. Despite these motions, hydrophobicity at the active site is maintained to facilitate VKOR catalysis. Biochemical experiments suggest that several warfarin-resistant mutations act by changing the conformation of the horizontal helix. Taken together, these studies provide a comprehensive understanding of VKOR function.

Structures of an intramembrane vitamin K epoxide reductase homolog reveal control mechanisms for electron transfer.,Liu S, Cheng W, Fowle Grider R, Shen G, Li W Nat Commun. 2014 Jan 29;5:3110. doi: 10.1038/ncomms4110. PMID:24477003<ref>PMID:24477003</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4nv5" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Cheng W]]
[[Category: Fowle Grider R]]
[[Category: Li W]]
[[Category: Liu S]]
[[Category: Shen G]]