View source for 6pq1


==Structure of the Fremyella diplosiphon OCP1==
<StructureSection load='6pq1' size='340' side='right'caption='[[6pq1]], [[Resolution|resolution]] 1.61&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6pq1]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Tolypothrix_sp._PCC_7601 Tolypothrix sp. PCC 7601]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6PQ1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6PQ1 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]] 1.61&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=45D:BETA,BETA-CAROTENE-4,4-DIONE'>45D</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=6pq1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6pq1 OCA], [https://pdbe.org/6pq1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6pq1 RCSB], [https://www.ebi.ac.uk/pdbsum/6pq1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6pq1 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A0D6KM24_9CYAN A0A0D6KM24_9CYAN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The orange carotenoid protein (OCP) is a structurally and functionally modular photoactive protein involved in cyanobacterial photoprotection. Recently, based on bioinformatic analysis and phylogenetic relationships, new families of OCP have been described, OCP2 and OCPx. The first characterization of the OCP2 showed both faster photoconversion and back-conversion, and lower fluorescence quenching of phycobilisomes relative to the well-characterized OCP1. Moreover, OCP2 is not regulated by the fluorescence recovery protein (FRP). In this work, we present a comprehensive study combining ultrafast spectroscopy and structural analysis to compare the photoactivation mechanisms of OCP1 and OCP2 from Tolypothrix PCC 7601. We show that despite significant differences in their functional characteristics, the spectroscopic properties of OCP1 and OCP2 are comparable. This indicates that the OCP functionality is not directly related to the spectroscopic properties of the bound carotenoid. In addition, the structural analysis by X-ray footprinting reveals that, overall, OCP1 and OCP2 have grossly the same photoactivation mechanism. However, the OCP2 is less reactive to radiolytic labeling, suggesting that the protein is less flexible than OCP1. This observation could explain fast photoconversion of OCP2.

Comparative ultrafast spectroscopy and structural analysis of OCP1 and OCP2 from Tolypothrix.,Kuznetsova V, Dominguez-Martin MA, Bao H, Gupta S, Sutter M, Kloz M, Rebarz M, Precek M, Chen Y, Petzold CJ, Ralston CY, Kerfeld CA, Polivka T Biochim Biophys Acta Bioenerg. 2020 Feb 1;1861(2):148120. doi:, 10.1016/j.bbabio.2019.148120. Epub 2019 Nov 14. PMID:31734194<ref>PMID:31734194</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6pq1" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Tolypothrix sp. PCC 7601]]
[[Category: Bao H]]
[[Category: Dominguez-Martin MA]]
[[Category: Kerfeld CA]]
[[Category: Sutter M]]