6ymx
From Proteopedia
CIII2/CIV respiratory supercomplex from Saccharomyces cerevisiae
Structural highlights
FunctionCOX1_YEAST Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Subunits 1-3 form the functional core of the enzyme complex. CO I is the catalytic subunit of the enzyme. Electrons originating in cytochrome c are transferred via the copper A center of subunit 2 and heme A of subunit 1 to the bimetallic center formed by heme A3 and copper B. Publication Abstract from PubMedRespiratory chains are crucial for cellular energy conversion and consist of multi-subunit complexes that can assemble into supercomplexes. These structures have been intensively characterized in various organisms, but their physiological roles remain unclear. Here, we elucidate their function by leveraging a high-resolution structural model of yeast respiratory supercomplexes that allowed us to inhibit supercomplex formation by mutation of key residues in the interaction interface. Analyses of a mutant defective in supercomplex formation, which still contains fully functional individual complexes, show that the lack of supercomplex assembly delays the diffusion of cytochrome c between the separated complexes, thus reducing electron transfer efficiency. Consequently, competitive cellular fitness is severely reduced in the absence of supercomplex formation and can be restored by overexpression of cytochrome c. In sum, our results establish how respiratory supercomplexes increase the efficiency of cellular energy conversion, thereby providing an evolutionary advantage for aerobic organisms. Respiratory supercomplexes enhance electron transport by decreasing cytochrome c diffusion distance.,Berndtsson J, Kohler A, Rathore S, Marin-Buera L, Dawitz H, Diessl J, Kohler V, Barrientos A, Buttner S, Fontanesi F, Ott M EMBO Rep. 2020 Dec 3;21(12):e51015. doi: 10.15252/embr.202051015. Epub 2020 Oct , 5. PMID:33016568[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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