View source for 5ek8


==Crystal structure of a 9R-lipoxygenase from Cyanothece PCC8801 at 2.7 Angstroms==
<StructureSection load='5ek8' size='340' side='right'caption='[[5ek8]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5ek8]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Rippkaea_orientalis_PCC_8801 Rippkaea orientalis PCC 8801]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5EK8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5EK8 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]] 2.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=5ek8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5ek8 OCA], [https://pdbe.org/5ek8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5ek8 RCSB], [https://www.ebi.ac.uk/pdbsum/5ek8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5ek8 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/B7K2Q5_RIPO1 B7K2Q5_RIPO1] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
In eukaryotes, oxidized polyunsaturated fatty acids, so-called oxylipins, are vital signaling molecules. The first step in their biosynthesis may be catalyzed by a lipoxygenase (LOX), which forms hydroperoxides by introducing dioxygen into polyunsaturated fatty acids. Here we characterized CspLOX1, a phylogenetically distant LOX family member from Cyanothece sp. PCC 8801 and determined its crystal structure. In addition to the classical two domains found in plant, animal and coral LOXs, we identified an N-terminal helical extension, reminiscent of the long alpha-helical insertion in Pseudomonas aeruginosa LOX. In liposome flotation studies, this helical extension rather than the beta-barrel domain was crucial for a membrane binding function. Additionally, CspLOX1 could oxygenate 1,2-diarachidonyl-sn-glycero-3-phosphocholine, suggesting that the enzyme may act directly on membranes and that fatty acids bind to the active site in a tail-first orientation. This binding mode is further supported by the fact that CspLOX1 catalyzed oxygenation at the n-10 position of both linoleic and arachidonic acid, resulting in 9R- and 11R-hydroperoxides, respectively. Together these results reveal unifying structural features of LOXs and their function. While the core of the active site is important for lipoxygenation and thus highly conserved, peripheral domains functioning in membrane and substrate binding are more variable.

Crystal structure of a lipoxygenase from Cyanothece sp. may reveal novel features for substrate acquisition.,Newie J, Andreou A, Neumann P, Einsle O, Feussner I, Ficner R J Lipid Res. 2015 Dec 14. pii: jlr.M064980. PMID:26667668<ref>PMID:26667668</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5ek8" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Rippkaea orientalis PCC 8801]]
[[Category: Andreou A]]
[[Category: Einsle O]]
[[Category: Feussner I]]
[[Category: Ficner R]]
[[Category: Neumann P]]
[[Category: Newie J]]