1yf6: Difference between revisions

<StructureSection load='1yf6' size='340' side='right'caption='[[1yf6]], [[Resolution|resolution]] 2.25&Aring;' scene=''>

<table><tr><td colspan='2'>[[1yf6]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Cereibacter_sphaeroides Cereibacter sphaeroides]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YF6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1YF6 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=BPH:BACTERIOPHEOPHYTIN+A'>BPH</scene>, <scene name='pdbligand=CDL:CARDIOLIPIN'>CDL</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=HTO:HEPTANE-1,2,3-TRIOL'>HTO</scene>, <scene name='pdbligand=LDA:LAURYL+DIMETHYLAMINE-N-OXIDE'>LDA</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene>, <scene name='pdbligand=SPO:SPHEROIDENE'>SPO</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=1yf6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1yf6 OCA], [https://pdbe.org/1yf6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1yf6 RCSB], [https://www.ebi.ac.uk/pdbsum/1yf6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1yf6 ProSAT]</span></td></tr>

[https://www.uniprot.org/uniprot/RCEL_CERSP RCEL_CERSP] The reaction center is a membrane-bound complex that mediates the initial photochemical event in the electron transfer process of photosynthesis.

    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/yf/1yf6_consurf.spt"</scriptWhenChecked>

    <text>to colour the structure by Evolutionary Conservation</text>

</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1yf6 ConSurf].

The photosynthetic reaction center (RC) from purple bacteria converts light into chemical energy. Although the RC shows two nearly structurally symmetric branches, A and B, light-induced electron transfer in the native RC occurs almost exclusively along the A-branch to a primary quinone electron acceptor Q(A). Subsequent electron and proton transfer to a mobile quinone molecule Q(B) converts it to a quinol, Q(B)H(2). We report the construction and characterization of a series of mutants in Rhodobacter sphaeroides designed to reduce Q(B) via the B-branch. The quantum efficiency to Q(B) via the B-branch Phi(B) ranged from 0.4% in an RC containing the single mutation Ala-M260 --&gt; Trp to 5% in a quintuple mutant which includes in addition three mutations to inhibit transfer along the A-branch (Gly-M203 --&gt; Asp, Tyr-M210 --&gt; Phe, Leu-M214 --&gt; His) and one to promote transfer along the B-branch (Phe-L181 --&gt; Tyr). Comparing the value of 0.4% for Phi(B) obtained in the AW(M260) mutant, which lacks Q(A), to the 100% quantum efficiency for Phi(A) along the A-branch in the native RC, we obtain a ratio for A-branch to B-branch electron transfer of 250:1. We determined the structure of the most effective (quintuple) mutant RC at 2.25 A (R-factor = 19.6%). The Q(A) site did not contain a quinone but was occupied by the side chain of Trp-M260 and a Cl(-). In this structure a nonfunctional quinone was found to occupy a new site near M258 and M268. The implications of this work to trap intermediate states are discussed.

Quinone (QB) reduction by B-branch electron transfer in mutant bacterial reaction centers from Rhodobacter sphaeroides: quantum efficiency and X-ray structure.,Paddock ML, Chang C, Xu Q, Abresch EC, Axelrod HL, Feher G, Okamura MY Biochemistry. 2005 May 10;44(18):6920-8. PMID:15865437<ref>PMID:15865437</ref>

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

</div>

<div class="pdbe-citations 1yf6" style="background-color:#fffaf0;"></div>

== References ==

<references/>

</StructureSection>

[[Category: Cereibacter sphaeroides]]

[[Category: Large Structures]]

[[Category: Abresch EC]]

[[Category: Axelrod HL]]

[[Category: Chang C]]

[[Category: Paddock ML]]

[[Category: Xu Q]]