7D6V

Mycobacterium smegmatis Sdh1 in complex with UQ1

Summary for 7D6V

• Entry DOI: 10.2210/pdb7d6v/pdb
• EMDB information: 30594
• Descriptor: Succinate dehydrogenase subunit A, Fumarate reductase iron-sulfur subunit, Succinate dehydrogenase (Membrane anchor subunit), ... (9 entities in total)
• Functional Keywords: succinate dehydrogenase, electron transport chain, mycobacterium smegmatis, sdh1, sqr, oxidoreductase
• Biological source: Mycolicibacterium smegmatis; More
• Total number of polymer chains: 3
• Total formula weight: 134337.64

Authors

Zhou, X.,Gao, Y.,Wang, Q.,Gong, H.,Rao, Z. (deposition date: 2020-10-02, release date: 2021-04-07, Last modification date: 2024-10-23)

Primary citation

Zhou, X.,Gao, Y.,Wang, W.,Yang, X.,Yang, X.,Liu, F.,Tang, Y.,Lam, S.M.,Shui, G.,Yu, L.,Tian, C.,Guddat, L.W.,Wang, Q.,Rao, Z.,Gong, H.
Architecture of the mycobacterial succinate dehydrogenase with a membrane-embedded Rieske FeS cluster.
Proc.Natl.Acad.Sci.USA, 118:-, 2021

PubMed Abstract: Complex II, also known as succinate dehydrogenase (SQR) or fumarate reductase (QFR), is an enzyme involved in both the Krebs cycle and oxidative phosphorylation. Mycobacterial Sdh1 has recently been identified as a new class of respiratory complex II (type F) but with an unknown electron transfer mechanism. Here, using cryoelectron microscopy, we have determined the structure of Sdh1 in the presence and absence of the substrate, ubiquinone-1, at 2.53-Å and 2.88-Å resolution, respectively. Sdh1 comprises three subunits, two that are water soluble, SdhA and SdhB, and one that is membrane spanning, SdhC. Within these subunits we identified a quinone-binding site and a rarely observed Rieske-type [2Fe-2S] cluster, the latter being embedded in the transmembrane region. A mutant, where two His ligands of the Rieske-type [2Fe-2S] were changed to alanine, abolished the quinone reduction activity of the Sdh1. Our structures allow the proposal of an electron transfer pathway that connects the substrate-binding and quinone-binding sites. Given the unique features of Sdh1 and its essential role in , these structures will facilitate antituberculosis drug discovery efforts that specifically target this complex.

PubMed: 33876763
DOI: 10.1073/pnas.2022308118

Experimental method

ELECTRON MICROSCOPY (2.53 Å)