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4f2z

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Revision as of 21:45, 5 August 2016

Crystal structure of RPE65 in a lipid environment

Structural highlights

4f2z is a 2 chain structure with sequence from Bos taurus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Related:	3fsn, 4f30, 4f3a, 4f3d
Activity:	Retinoid isomerohydrolase, with EC number 3.1.1.64
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[RPE65_BOVIN] Plays important roles in the production of 11-cis retinal and in visual pigment regeneration. The soluble form binds vitamin A (all-trans-retinol), making it available for LRAT processing to all-trans-retinyl ester. The membrane form, palmitoylated by LRAT, binds all-trans-retinyl esters, making them available for IMH (isomerohydrolase) processing to all-cis-retinol. The soluble form is regenerated by transferring its palmitoyl groups onto 11-cis-retinol, a reaction catalyzed by LRAT. The enzymatic activity is linearly dependent of the expression levels and membrane association.^[1] ^[2] ^[3]

Publication Abstract from PubMed

RPE65 is a key metalloenzyme responsible for maintaining visual function in vertebrates. Despite extensive research on this membrane-bound retinoid isomerase, fundamental questions regarding its enzymology remain unanswered. Here, we report the crystal structure of RPE65 in a membrane-like environment. These crystals, obtained from enzymatically active, nondelipidated protein, displayed an unusual packing arrangement wherein RPE65 is embedded in a lipid-detergent sheet. Structural differences between delipidated and nondelipidated RPE65 uncovered key residues involved in substrate uptake and processing. Complementary iron K-edge X-ray absorption spectroscopy data established that RPE65 as isolated contained a divalent iron center and demonstrated the presence of a tightly bound ligand consistent with a coordinated carboxylate group. These results support the hypothesis that the Lewis acidity of iron could be used to promote ester dissociation and generation of a carbocation intermediate required for retinoid isomerization.

Structure of RPE65 isomerase in a lipidic matrix reveals roles for phospholipids and iron in catalysis.,Kiser PD, Farquhar ER, Shi W, Sui X, Chance MR, Palczewski K Proc Natl Acad Sci U S A. 2012 Oct 9;109(41):E2747-56. doi:, 10.1073/pnas.1212025109. Epub 2012 Sep 24. PMID:23012475^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Jin M, Li S, Moghrabi WN, Sun H, Travis GH. Rpe65 is the retinoid isomerase in bovine retinal pigment epithelium. Cell. 2005 Aug 12;122(3):449-59. PMID:16096063 doi:10.1016/j.cell.2005.06.042
↑ Kiser PD, Golczak M, Lodowski DT, Chance MR, Palczewski K. Crystal structure of native RPE65, the retinoid isomerase of the visual cycle. Proc Natl Acad Sci U S A. 2009 Oct 13;106(41):17325-30. Epub 2009 Oct 5. PMID:19805034
↑ Golczak M, Kiser PD, Lodowski DT, Maeda A, Palczewski K. Importance of membrane structural integrity for RPE65 retinoid isomerization activity. J Biol Chem. 2010 Mar 26;285(13):9667-82. Epub 2010 Jan 25. PMID:20100834 doi:10.1074/jbc.M109.063941
↑ Kiser PD, Farquhar ER, Shi W, Sui X, Chance MR, Palczewski K. Structure of RPE65 isomerase in a lipidic matrix reveals roles for phospholipids and iron in catalysis. Proc Natl Acad Sci U S A. 2012 Oct 9;109(41):E2747-56. doi:, 10.1073/pnas.1212025109. Epub 2012 Sep 24. PMID:23012475 doi:http://dx.doi.org/10.1073/pnas.1212025109

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4f2z"

@@ Line 1: / Line 1: @@
 ==Crystal structure of RPE65 in a lipid environment==
 <StructureSection load='4f2z' size='340' side='right' caption='[[4f2z]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
@@ Line 6: / Line 7: @@
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3fsn|3fsn]], [[4f30|4f30]], [[4f3a|4f3a]], [[4f3d|4f3d]]</td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Retinoid_isomerohydrolase Retinoid isomerohydrolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.64 3.1.1.64] </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=4f2z FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4f2z OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4f2z RCSB], [http://www.ebi.ac.uk/pdbsum/4f2z PDBsum]</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=4f2z FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4f2z OCA], [http://pdbe.org/4f2z PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4f2z RCSB], [http://www.ebi.ac.uk/pdbsum/4f2z PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4f2z ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 18: / Line 19: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 4f2z" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

4f2z

From Proteopedia

Revision as of 21:45, 5 August 2016

Crystal structure of RPE65 in a lipid environment

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

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