2hq8

<table><tr><td colspan='2'>[[2hq8]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Mueller's_sea_pansy Mueller's sea pansy]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2HQ8 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2HQ8 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2hps|2hps]]</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=2hq8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2hq8 OCA], [http://pdbe.org/2hq8 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2hq8 RCSB], [http://www.ebi.ac.uk/pdbsum/2hq8 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2hq8 ProSAT], [http://www.topsan.org/Proteins/SECSG/2hq8 TOPSAN]</span></td></tr>

[[http://www.uniprot.org/uniprot/LBP_RENRE LBP_RENRE]] This Ca(2+)-dependent protein binds to luciferin. The luciferin of LBP is capable of reacting with luciferase and O(2) only when calcium is bound.

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== Publication Abstract from PubMed ==

Bioluminescence in the sea pansy Renilla involves two distinct proteins, a Ca2+-triggered coelenterazine-binding protein (CBP), and Renilla luciferase. CBP contains one tightly bound coelenterazine molecule, which becomes available for reaction with luciferase and O2 only subsequent to Ca2+ binding. CBP belongs to the EF-hand superfamily of Ca2+-binding proteins and contains three "EF-hand" Ca2+-binding sites. The overall spatial structure of recombinant selenomethionine-labeled CBP determined at 1.7 A, is found to approximate the protein scaffold characteristic of the class of Ca2+-regulated photoproteins. Photoproteins however, catalyze molecular oxygen addition to coelenterazine producing a 2-hydroperoxycoelenterazine intermediate, which is stabilized within the binding cavity in the absence of Ca2+. Addition of Ca2+ triggers the bioluminescence reaction. However in CBP this first step of oxygen addition is not allowed. The different amino acid environments and hydrogen bond interactions within the binding cavity, are proposed to account for the different properties of the two classes of proteins.

Crystal structure of coelenterazine-binding protein from Renilla muelleri at 1.7 A: why it is not a calcium-regulated photoprotein.,Stepanyuk GA, Liu ZJ, Markova SS, Frank LA, Lee J, Vysotski ES, Wang BC Photochem Photobiol Sci. 2008 Apr;7(4):442-7. Epub 2008 Feb 19. PMID:18385886<ref>PMID:18385886</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Mueller's sea pansy]]

[[Category: Lee, J]]

[[Category: Liu, Z J]]

[[Category: Rose, J P]]

[[Category: Structural genomic]]

[[Category: Stepanyuk, G]]

[[Category: Vysotski, E S]]

[[Category: Wang, B C]]

[[Category: Coelenterazine-binding protein]]

[[Category: PSI, Protein structure initiative]]

[[Category: Secsg]]

[[Category: Unknown function]]