View source for 8gth


==Crystal strucuture of cyt c551 from anoxygenic phototrophic bacterium Roseiflexus castenholzii==
<StructureSection load='8gth' size='340' side='right'caption='[[8gth]], [[Resolution|resolution]] 3.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8gth]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Roseiflexus_castenholzii_DSM_13941 Roseiflexus castenholzii DSM 13941]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8GTH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8GTH 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]] 3.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=HEC:HEME+C'>HEC</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=8gth FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8gth OCA], [https://pdbe.org/8gth PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8gth RCSB], [https://www.ebi.ac.uk/pdbsum/8gth PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8gth ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A7NME2_ROSCS A7NME2_ROSCS] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Roseiflexus castenholzii is a gram-negative filamentous phototrophic bacterium that carries out anoxygenic photosynthesis through a cyclic electron transport chain (ETC). The ETC is composed of a reaction center (RC)-light-harvesting (LH) complex (rcRC-LH); an alternative complex III (rcACIII), which functionally replaces the cytochrome bc(1)/b(6)f complex; and the periplasmic electron acceptor auracyanin (rcAc). Although compositionally and structurally different from the bc(1)/b(6)f complex, rcACIII plays similar essential roles in oxidizing menaquinol and transferring electrons to the rcAc. However, rcACIII-mediated electron transfer (which includes both an intraprotein route and a downstream route) has not been clearly elucidated, nor have the details of cyclic ETC. Here, we identify a previously unknown monoheme cytochrome c (cyt c(551)) as a novel periplasmic electron acceptor of rcACIII. It reduces the light-excited rcRC-LH to complete a cyclic ETC. We also reveal the molecular mechanisms involved in the ETC using electron paramagnetic resonance (EPR), spectroelectrochemistry, and enzymatic and structural analyses. We find that electrons released from rcACIII-oxidized menaquinol are transferred to two alternative periplasmic electron acceptors (rcAc and cyt c(551)), which eventually reduce the rcRC to form the complete cyclic ETC. This work serves as a foundation for further studies of ACIII-mediated electron transfer in anoxygenic photosynthesis and broadens our understanding of the diversity and molecular evolution of prokaryotic ETCs.

A cytochrome c(551) mediates the cyclic electron transport chain of the anoxygenic phototrophic bacterium Roseiflexus castenholzii.,Yu L, Min Z, Liu M, Xin Y, Liu A, Kuang J, Wu W, Wu J, He H, Xin J, Blankenship RE, Tian C, Xu X Plant Commun. 2024 Feb 12;5(2):100715. doi: 10.1016/j.xplc.2023.100715. Epub 2023 , Sep 14. PMID:37710959<ref>PMID:37710959</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8gth" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Roseiflexus castenholzii DSM 13941]]
[[Category: Meng HL]]
[[Category: Min ZZ]]
[[Category: Xu XL]]