View source for 7p92


==TmHydABC- T. maritima bifurcating hydrogenase with bridge domain up==
<StructureSection load='7p92' size='340' side='right'caption='[[7p92]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7p92]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermotoga_maritima_MSB8 Thermotoga maritima MSB8]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7P92 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7P92 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]] 2.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FES:FE2/S2+(INORGANIC)+CLUSTER'>FES</scene>, <scene name='pdbligand=FMN:FLAVIN+MONONUCLEOTIDE'>FMN</scene>, <scene name='pdbligand=SF4:IRON/SULFUR+CLUSTER'>SF4</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=7p92 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7p92 OCA], [https://pdbe.org/7p92 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7p92 RCSB], [https://www.ebi.ac.uk/pdbsum/7p92 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7p92 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/HYDA_THEMA HYDA_THEMA] Catalyzes the oxidation of the physiological electron carriers NADH and reduced ferredoxin, coupled to the production of H(2) (PubMed:19411328). Acts as a bifurcating [FeFe] hydrogenase, which uses the exergonic oxidation of reduced ferredoxin to drive the unfavorable oxidation of NADH to produce H(2) (PubMed:19411328). The alpha subunit contains the catalytic H-cluster (PubMed:19411328).<ref>PMID:19411328</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Electron bifurcation is a fundamental energy conservation mechanism in nature in which two electrons from an intermediate-potential electron donor are split so that one is sent along a high-potential pathway to a high-potential acceptor and the other is sent along a low-potential pathway to a low-potential acceptor. This process allows endergonic reactions to be driven by exergonic ones and is an alternative, less recognized, mechanism of energy coupling to the well-known chemiosmotic principle. The electron-bifurcating [FeFe] hydrogenase from Thermotoga maritima (HydABC) requires both NADH and ferredoxin to reduce protons generating hydrogen. The mechanism of electron bifurcation in HydABC remains enigmatic in spite of intense research efforts over the last few years. Structural information may provide the basis for a better understanding of spectroscopic and functional information. Here, we present a 2.3 A electron cryo-microscopy structure of HydABC. The structure shows a heterododecamer composed of two independent 'halves' each made of two strongly interacting HydABC heterotrimers connected via a [4Fe-4S] cluster. A central electron transfer pathway connects the active sites for NADH oxidation and for proton reduction. We identified two conformations of a flexible iron-sulfur cluster domain: a 'closed bridge' and an 'open bridge' conformation, where a Zn(2+) site may act as a 'hinge' allowing domain movement. Based on these structural revelations, we propose a possible mechanism of electron bifurcation in HydABC where the flavin mononucleotide serves a dual role as both the electron bifurcation center and as the NAD(+) reduction/NADH oxidation site.

Structural insight on the mechanism of an electron-bifurcating [FeFe] hydrogenase.,Furlan C, Chongdar N, Gupta P, Lubitz W, Ogata H, Blaza JN, Birrell JA Elife. 2022 Aug 26;11:e79361. doi: 10.7554/eLife.79361. PMID:36018003<ref>PMID:36018003</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7p92" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Thermotoga maritima MSB8]]
[[Category: Birrell JA]]
[[Category: Blaza JN]]
[[Category: Chongdar N]]
[[Category: Furlan C]]
[[Category: Gupta P]]
[[Category: Lubitz W]]
[[Category: Ogata H]]