View source for 9ihq


==Closed state with NUQM and without flavoprotein (classification state 2) of Pichia pastoris mitochondrial complex I in cMSP26 nanodiscs==
<StructureSection load='9ihq' size='340' side='right'caption='[[9ihq]], [[Resolution|resolution]] 2.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ihq]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Komagataella_pastoris Komagataella pastoris]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9IHQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9IHQ 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]] 2.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=2MR:N3,+N4-DIMETHYLARGININE'>2MR</scene>, <scene name='pdbligand=3PE:1,2-DIACYL-SN-GLYCERO-3-PHOSPHOETHANOLAMINE'>3PE</scene>, <scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</scene>, <scene name='pdbligand=CDL:CARDIOLIPIN'>CDL</scene>, <scene name='pdbligand=EHZ:~{S}-[2-[3-[[(2~{R})-3,3-dimethyl-2-oxidanyl-4-phosphonooxy-butanoyl]amino]propanoylamino]ethyl]+(3~{S})-3-oxidanyltetradecanethioate'>EHZ</scene>, <scene name='pdbligand=FES:FE2/S2+(INORGANIC)+CLUSTER'>FES</scene>, <scene name='pdbligand=FME:N-FORMYLMETHIONINE'>FME</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=NDP:NADPH+DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NDP</scene>, <scene name='pdbligand=PLC:DIUNDECYL+PHOSPHATIDYL+CHOLINE'>PLC</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=9ihq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ihq OCA], [https://pdbe.org/9ihq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ihq RCSB], [https://www.ebi.ac.uk/pdbsum/9ihq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ihq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/AIM41_KOMPG AIM41_KOMPG] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Complex I (CI; NADH ubiquinone oxidoreductase) is central to energy generation and metabolic homeostasis in mammalian cells but contributes to adverse outcome pathways under challenging conditions. During ischemia, mammalian CI transitions from a turnover-ready, structurally "closed" state toward a dormant "open" state that prevents it from functioning in reverse during reperfusion to produce reactive oxygen species. Unfortunately, simpler, genetically tractable CI models do not recapitulate the same regulatory behavior, compromising mechanistic studies. Here, we report the structure of isolated CI from the yeast Pichia pastoris (Pp-CI) and identify distinct closed and open states that resemble those of mammalian CI. Notably, a hitherto-unknown protein (NUQM) completes an interdomain bridge in only the closed state, implying that NUQM stabilizes it by restricting the conformational changes of opening. The direct correlation of NUQM binding with closed/open status in Pp-CI provides opportunities for investigating regulatory mechanisms relevant to reversible catalysis and ischemia-reperfusion injury.

Global conformations of Pichia pastoris complex I are distinguished by the binding of a unique interdomain bridging subunit.,Lee CS, Grba DN, Wright JJ, Ivanov BS, Hirst J Sci Adv. 2025 Oct 3;11(40):eadz0693. doi: 10.1126/sciadv.adz0693. Epub 2025 Oct , 1. PMID:41032597<ref>PMID:41032597</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9ihq" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Komagataella pastoris]]
[[Category: Large Structures]]
[[Category: Grba DN]]
[[Category: Hirst J]]