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4pv1

From Proteopedia

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Current revision

Cytochrome B6F structure from M. laminosus with the quinone analog inhibitor stigmatellin

Structural highlights

4pv1 is a 8 chain structure with sequence from Mastigocladus laminosus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, , , , , , , , , , ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

CYB6_MASLA Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions.[HAMAP-Rule:MF_00633]

Publication Abstract from PubMed

The cytochrome bc complexes b6f and bc1 catalyze proton-coupled quinol/quinone redox reactions to generate a transmembrane proton electrochemical gradient. Quinol oxidation on the electrochemically positive (p) interface of the complex occurs at the end of a narrow quinol/quinone entry/exit Qp portal, 11 A long in bc complexes. Superoxide, which has multiple signaling functions, is a by-product of the p-side quinol oxidation. Although the transmembrane core and the chemistry of quinone redox reactions are conserved in bc complexes, the rate of superoxide generation is an order of magnitude greater in the b6f complex, implying that functionally significant differences in structure exist between the b6f and bc1 complexes on the p-side. A unique structure feature of the b6f p-side quinol oxidation site is the presence of a single chlorophyll-a molecule whose function is unrelated to light harvesting. This study describes a cocrystal structure of the cytochrome b6f complex with the quinol analog stigmatellin, which partitions in the Qp portal of the bc1 complex, but not effectively in b6f. It is inferred that the Qp portal is partially occluded in the b6f complex relative to bc1. Based on a discrete molecular-dynamics analysis, occlusion of the Qp portal is attributed to the presence of the chlorophyll phytyl tail, which increases the quinone residence time within the Qp portal and is inferred to be a cause of enhanced superoxide production. This study attributes a novel (to our knowledge), structure-linked function to the otherwise enigmatic chlorophyll-a in the b6f complex, which may also be relevant to intracellular redox signaling.

Traffic within the cytochrome b6f lipoprotein complex: gating of the quinone portal.,Hasan SS, Proctor EA, Yamashita E, Dokholyan NV, Cramer WA Biophys J. 2014 Oct 7;107(7):1620-8. doi: 10.1016/j.bpj.2014.08.003. PMID:25296314^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Hasan SS, Proctor EA, Yamashita E, Dokholyan NV, Cramer WA. Traffic within the cytochrome b6f lipoprotein complex: gating of the quinone portal. Biophys J. 2014 Oct 7;107(7):1620-8. doi: 10.1016/j.bpj.2014.08.003. PMID:25296314 doi:http://dx.doi.org/10.1016/j.bpj.2014.08.003

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4pv1"

Categories: Large Structures | Mastigocladus laminosus | Cramer WA | Hasan SS | Yamashita E

@@ Line 5: / Line 5: @@
 <table><tr><td colspan='2'>[[4pv1]] is a 8 chain structure with sequence from [https://en.wikipedia.org/wiki/Mastigocladus_laminosus Mastigocladus laminosus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4PV1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4PV1 FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=7PH:(1R)-2-(DODECANOYLOXY)-1-[(PHOSPHONOOXY)METHYL]ETHYL+TETRADECANOATE'>7PH</scene>, <scene name='pdbligand=8K6:OCTADECANE'>8K6</scene>, <scene name='pdbligand=BCR:BETA-CAROTENE'>BCR</scene>, <scene name='pdbligand=CD:CADMIUM+ION'>CD</scene>, <scene name='pdbligand=CLA:CHLOROPHYLL+A'>CLA</scene>, <scene name='pdbligand=FES:FE2/S2+(INORGANIC)+CLUSTER'>FES</scene>, <scene name='pdbligand=HEC:HEME+C'>HEC</scene>, <scene name='pdbligand=MYS:PENTADECANE'>MYS</scene>, <scene name='pdbligand=OPC:(7R,17E)-4-HYDROXY-N,N,N,7-TETRAMETHYL-7-[(8E)-OCTADEC-8-ENOYLOXY]-10-OXO-3,5,9-TRIOXA-4-PHOSPHAHEPTACOS-17-EN-1-AMINIUM+4-OXIDE'>OPC</scene>, <scene name='pdbligand=SMA:STIGMATELLIN+A'>SMA</scene>, <scene name='pdbligand=SQD:1,2-DI-O-ACYL-3-O-[6-DEOXY-6-SULFO-ALPHA-D-GLUCOPYRANOSYL]-SN-GLYCEROL'>SQD</scene>, <scene name='pdbligand=UMQ:UNDECYL-MALTOSIDE'>UMQ</scene></td></tr>
-<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1vf5|1vf5]], [[1q90|1q90]], [[2e74|2e74]], [[2e75|2e75]], [[2e76|2e76]], [[2zt9|2zt9]], [[4h44|4h44]], [[4h13|4h13]], [[4h0l|4h0l]], [[3cx5|3cx5]], [[4ogq|4ogq]]</div></td></tr>
-<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Plastoquinol--plastocyanin_reductase Plastoquinol--plastocyanin reductase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.10.9.1 1.10.9.1] </span></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=4pv1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4pv1 OCA], [https://pdbe.org/4pv1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4pv1 RCSB], [https://www.ebi.ac.uk/pdbsum/4pv1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4pv1 ProSAT]</span></td></tr>
 </table>
 == Function ==
-[[https://www.uniprot.org/uniprot/PETM_MASLA PETM_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions. [[https://www.uniprot.org/uniprot/CYF_MASLA CYF_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions. [[https://www.uniprot.org/uniprot/PETG_MASLA PETG_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions. PetG is required for either the stability or assembly of the cytochrome b6-f complex. [[https://www.uniprot.org/uniprot/PETD_MASLA PETD_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions. [[https://www.uniprot.org/uniprot/PETN_MASLA PETN_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions. [[https://www.uniprot.org/uniprot/CYB6_MASLA CYB6_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions.[HAMAP-Rule:MF_00633] [[https://www.uniprot.org/uniprot/UCRI_MASLA UCRI_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions. [[https://www.uniprot.org/uniprot/PETL_MASLA PETL_MASLA]] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions. PetL is important for photoautotrophic growth as well as for electron transfer efficiency and stability of the cytochrome b6-f complex.
+[https://www.uniprot.org/uniprot/CYB6_MASLA CYB6_MASLA] Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions.[HAMAP-Rule:MF_00633]
 <div style="background-color:#fffaf0;">
 == Publication Abstract from PubMed ==
@@ Line 29: / Line 27: @@
 [[Category: Large Structures]]
 [[Category: Mastigocladus laminosus]]
-[[Category: Plastoquinol--plastocyanin reductase]]
+[[Category: Cramer WA]]
-[[Category: Cramer, W A]]
+[[Category: Hasan SS]]
-[[Category: Hasan, S S]]
+[[Category: Yamashita E]]
-[[Category: Yamashita, E]]
-[[Category: Alpha helix]]
-[[Category: Beta sheet]]
-[[Category: Electron transport-inhibitor complex]]
-[[Category: Plastocyanin]]
-[[Category: Plastoquinol:plastocyanin oxidoreductase]]
-[[Category: Thylakoid membrane]]

4pv1

From Proteopedia

Current revision

Cytochrome B6F structure from M. laminosus with the quinone analog inhibitor stigmatellin

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

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