View source for 3weg


==Crystal structure of the human squalene synthase in complex with farnesyl thiopyrophosphate and magnesium ion==
<StructureSection load='3weg' size='340' side='right'caption='[[3weg]], [[Resolution|resolution]] 1.75&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3weg]] is a 1 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=3WEG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3WEG 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]] 1.75&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FPS:S-[(2E,6E)-3,7,11-TRIMETHYLDODECA-2,6,10-TRIENYL]+TRIHYDROGEN+THIODIPHOSPHATE'>FPS</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=3weg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3weg OCA], [https://pdbe.org/3weg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3weg RCSB], [https://www.ebi.ac.uk/pdbsum/3weg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3weg ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/FDFT_HUMAN FDFT_HUMAN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Squalene synthase (SQS) is a divalent metal-ion-dependent enzyme that catalyzes the two-step reductive `head-to-head' condensation of two molecules of farnesyl pyrophosphate to form squalene using presqualene diphosphate (PSPP) as an intermediate. In this paper, the structures of human SQS and its mutants in complex with several substrate analogues and intermediates coordinated with Mg2+ or Mn2+ are presented, which stepwise delineate the biosynthetic pathway. Extensive study of the SQS active site has identified several critical residues that are involved in binding reduced nicotinamide dinucleotide phosphate (NADPH). Based on mutagenesis data and a locally closed (JK loop-in) structure observed in the hSQS-(F288L)-PSPP complex, an NADPH-binding model is proposed for SQS. The results identified four major steps (substrate binding, condensation, intermediate formation and translocation) of the ordered sequential mechanisms involved in the `1'-1' isoprenoid biosynthetic pathway. These new findings clarify previous hypotheses based on site-directed mutagenesis and biochemical analysis.

Structural insights into the catalytic mechanism of human squalene synthase.,Liu CI, Jeng WY, Chang WJ, Shih MF, Ko TP, Wang AH Acta Crystallogr D Biol Crystallogr. 2014 Feb;70(Pt 2):231-41. doi:, 10.1107/S1399004713026230. Epub 2014 Jan 17. PMID:24531458<ref>PMID:24531458</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3weg" style="background-color:#fffaf0;"></div>

==See Also==
*[[Squalene synthase|Squalene synthase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Jeng WY]]
[[Category: Liu CI]]
[[Category: Wang AHJ]]