View source for 9kzh


==Cryo-EM structure of the RC complex from Rhodospirillum rubrum==
<StructureSection load='9kzh' size='340' side='right'caption='[[9kzh]], [[Resolution|resolution]] 2.74&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9kzh]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Rhodospirillum_rubrum Rhodospirillum rubrum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9KZH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9KZH FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 2.74&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=8K6:OCTADECANE'>8K6</scene>, <scene name='pdbligand=CDL:CARDIOLIPIN'>CDL</scene>, <scene name='pdbligand=CRT:SPIRILLOXANTHIN'>CRT</scene>, <scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=LMT:DODECYL-BETA-D-MALTOSIDE'>LMT</scene>, <scene name='pdbligand=PEF:DI-PALMITOYL-3-SN-PHOSPHATIDYLETHANOLAMINE'>PEF</scene>, <scene name='pdbligand=PGV:(1R)-2-{[{[(2S)-2,3-DIHYDROXYPROPYL]OXY}(HYDROXY)PHOSPHORYL]OXY}-1-[(PALMITOYLOXY)METHYL]ETHYL+(11E)-OCTADEC-11-ENOATE'>PGV</scene>, <scene name='pdbligand=RQ0:2-azanyl-5-[(2~{E},6~{E},8~{E},10~{E},12~{E},14~{E},18~{E},22~{E},26~{E},30~{E},34~{E})-3,7,11,15,19,23,27,31,35,39-decamethyltetraconta-2,6,8,10,12,14,18,22,26,30,34,38-dodecaenyl]-3-methoxy-6-methyl-cyclohexa-2,5-diene-1,4-dione'>RQ0</scene>, <scene name='pdbligand=U10:UBIQUINONE-10'>U10</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=9kzh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9kzh OCA], [https://pdbe.org/9kzh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9kzh RCSB], [https://www.ebi.ac.uk/pdbsum/9kzh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9kzh ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RCEL_RHORU RCEL_RHORU] The reaction center is a membrane-bound complex that mediates the initial photochemical event in the electron transfer process of photosynthesis.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Photosynthetic complexes comprising light-harvesting (LH) and reaction center (RC) components are essential for biological energy conversion in photosynthesis. Assembly of these multi-protein structures is a topic of great interest, and assembly mechanisms appear to reflect the evolutionary diversity of the particular phototrophic organism. Here we constructed a photosynthetic chimera expressing the Roseiflexus castenholzii LH and Rhodospirillum rubrum RC complexes in a photocomplex-deficient Rsp. rubrum mutant, and spectroscopy confirmed LH expression with absorption maxima at 878 and 801 nm. The chimeric strain grew slower phototrophically than wildtype but faster than a strain containing only the RC, indicating partial energy transfer from LH to RC. Cryo-EM structural analysis revealed that the Rfl. castenholzii LH independently assembled into a closed ring of 15 alphabeta heterodimers lacking carotenoids, resulting in a blue-shifted Q(y) transition, while the Rsp. rubrum RC formed a separate complex with an RC:LH ratio of approximately 17:1 instead of a typical 1:1. Structural differences, including the absence of two Rfl. castenholzii-specific small proteins, likely precluded formation of a conjoined LH-RC in the chimeric strain. These results reveal that distinct photocomplex assembly strategies exist in phylogenetically divergent species and underscore the modularity and adaptability of photosynthetic complexes, offering insights for artificial photosystem design.

Assembly, selectivity, and compatibility of bacterial photosynthetic complexes from divergent species detected in a chimeric strain.,Wang L, Yan YH, Wang GL, Yue XY, Qi CH, Zou MJ, Wang-Otomo ZY, Madigan MT, Xin Y, Yu LJ Biochim Biophys Acta Bioenerg. 2026 Jan 27;1867(2):149584. doi: , 10.1016/j.bbabio.2026.149584. PMID:41611047<ref>PMID:41611047</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9kzh" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Rhodospirillum rubrum]]
[[Category: Wang L]]
[[Category: Yu L-J]]