View source for 7cou


==Structure of cyanobacterial photosystem II in the dark S1 state==
<StructureSection load='7cou' size='340' side='right'caption='[[7cou]], [[Resolution|resolution]] 2.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7cou]] is a 20 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermostichus_vulcanus Thermostichus vulcanus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7COU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7COU 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]] 2.25&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BCR:BETA-CAROTENE'>BCR</scene>, <scene name='pdbligand=BCT:BICARBONATE+ION'>BCT</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=CLA:CHLOROPHYLL+A'>CLA</scene>, <scene name='pdbligand=DGD:DIGALACTOSYL+DIACYL+GLYCEROL+(DGDG)'>DGD</scene>, <scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene>, <scene name='pdbligand=FME:N-FORMYLMETHIONINE'>FME</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=HEC:HEME+C'>HEC</scene>, <scene name='pdbligand=HTG:HEPTYL+1-THIOHEXOPYRANOSIDE'>HTG</scene>, <scene name='pdbligand=LHG:1,2-DIPALMITOYL-PHOSPHATIDYL-GLYCEROLE'>LHG</scene>, <scene name='pdbligand=LMG:1,2-DISTEAROYL-MONOGALACTOSYL-DIGLYCERIDE'>LMG</scene>, <scene name='pdbligand=LMT:DODECYL-BETA-D-MALTOSIDE'>LMT</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PHO:PHEOPHYTIN+A'>PHO</scene>, <scene name='pdbligand=PL9:2,3-DIMETHYL-5-(3,7,11,15,19,23,27,31,35-NONAMETHYL-2,6,10,14,18,22,26,30,34-HEXATRIACONTANONAENYL-2,5-CYCLOHEXADIENE-1,4-DIONE-2,3-DIMETHYL-5-SOLANESYL-1,4-BENZOQUINONE'>PL9</scene>, <scene name='pdbligand=SQD:1,2-DI-O-ACYL-3-O-[6-DEOXY-6-SULFO-ALPHA-D-GLUCOPYRANOSYL]-SN-GLYCEROL'>SQD</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=7cou FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7cou OCA], [https://pdbe.org/7cou PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7cou RCSB], [https://www.ebi.ac.uk/pdbsum/7cou PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7cou ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PSBA_THEVL PSBA_THEVL] D1 (PsbA) and D2 (PsbD) bind P680, the primary electron donor of photosystem II (PSII) as well as electron acceptors. PSII is a light-driven water plastoquinone oxidoreductase, using light energy to abstract electrons from H(2)O, generating a proton gradient subsequently used for ATP formation.[HAMAP-Rule:MF_01379]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Photosystem II (PSII) catalyzes light-induced water oxidation through an S (i) -state cycle, leading to the generation of di-oxygen, protons and electrons. Pump-probe time-resolved serial femtosecond crystallography (TR-SFX) has been used to capture structural dynamics of light-sensitive proteins. In this approach, it is crucial to avoid light contamination in the samples when analyzing a particular reaction intermediate. Here, a method for determining a condition that avoids light contamination of the PSII microcrystals while minimizing sample consumption in TR-SFX is described. By swapping the pump and probe pulses with a very short delay between them, the structural changes that occur during the S(1)-to-S(2) transition were examined and a boundary of the excitation region was accurately determined. With the sample flow rate and concomitant illumination conditions determined, the S(2)-state structure of PSII could be analyzed at room temperature, revealing the structural changes that occur during the S(1)-to-S(2) transition at ambient temperature. Though the structure of the manganese cluster was similar to previous studies, the behaviors of the water molecules in the two channels (O1 and O4 channels) were found to be different. By comparing with the previous studies performed at low temperature or with a different delay time, the possible channels for water inlet and structural changes important for the water-splitting reaction were revealed.

Capturing structural changes of the S(1) to S(2) transition of photosystem II using time-resolved serial femtosecond crystallography.,Li H, Nakajima Y, Nomura T, Sugahara M, Yonekura S, Chan SK, Nakane T, Yamane T, Umena Y, Suzuki M, Masuda T, Motomura T, Naitow H, Matsuura Y, Kimura T, Tono K, Owada S, Joti Y, Tanaka R, Nango E, Akita F, Kubo M, Iwata S, Shen JR, Suga M IUCrJ. 2021 Apr 7;8(Pt 3):431-443. doi: 10.1107/S2052252521002177. eCollection , 2021 May 1. PMID:33953929<ref>PMID:33953929</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7cou" style="background-color:#fffaf0;"></div>

==See Also==
*[[Photosystem II 3D structures|Photosystem II 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Thermostichus vulcanus]]
[[Category: Li H]]
[[Category: Shen J-R]]
[[Category: Suga M]]