ID COX3_SCHCO Reviewed; 268 AA. AC P14058; DT 01-JAN-1990, integrated into UniProtKB/Swiss-Prot. DT 01-FEB-1996, sequence version 2. DT 22-FEB-2023, entry version 102. DE RecName: Full=Cytochrome c oxidase subunit 3; DE EC=7.1.1.9; DE AltName: Full=Cytochrome c oxidase polypeptide III; GN Name=COIII; OS Schizophyllum commune (Split gill fungus). OG Mitochondrion. OC Eukaryota; Fungi; Dikarya; Basidiomycota; Agaricomycotina; Agaricomycetes; OC Agaricomycetidae; Agaricales; Schizophyllaceae; Schizophyllum. OX NCBI_TaxID=5334; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RX PubMed=3214878; DOI=10.1007/bf00419999; RA Phelps L.G., Burke J.M., Ullrich R.C., Novotny C.P.; RT "Nucleotide base sequence of the mitochondrial COIII gene of Schizophyllum RT commune."; RL Curr. Genet. 14:401-403(1988). CC -!- FUNCTION: Component of the cytochrome c oxidase, the last enzyme in the CC mitochondrial electron transport chain which drives oxidative CC phosphorylation. The respiratory chain contains 3 multisubunit CC complexes succinate dehydrogenase (complex II, CII), ubiquinol- CC cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CC CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to CC transfer electrons derived from NADH and succinate to molecular oxygen, CC creating an electrochemical gradient over the inner membrane that CC drives transmembrane transport and the ATP synthase. Cytochrome c CC oxidase is the component of the respiratory chain that catalyzes the CC reduction of oxygen to water. Electrons originating from reduced CC cytochrome c in the intermembrane space (IMS) are transferred via the CC dinuclear copper A center (CU(A)) of subunit 2 and heme A of subunit 1 CC to the active site in subunit 1, a binuclear center (BNC) formed by CC heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2 CC water molecules using 4 electrons from cytochrome c in the IMS and 4 CC protons from the mitochondrial matrix. {ECO:0000250|UniProtKB:P00420}. CC -!- CATALYTIC ACTIVITY: CC Reaction=4 Fe(II)-[cytochrome c] + 8 H(+)(in) + O2 = 4 Fe(III)- CC [cytochrome c] + 4 H(+)(out) + 2 H2O; Xref=Rhea:RHEA:11436, CC Rhea:RHEA-COMP:10350, Rhea:RHEA-COMP:14399, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:29033, CC ChEBI:CHEBI:29034; EC=7.1.1.9; CC Evidence={ECO:0000250|UniProtKB:P00420}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:11437; CC Evidence={ECO:0000250|UniProtKB:P00420}; CC -!- SUBUNIT: Component of the cytochrome c oxidase (complex IV, CIV), a CC multisubunit enzyme composed of a catalytic core of 3 subunits and CC several supernumerary subunits. The complex exists as a monomer or a CC dimer and forms supercomplexes (SCs) in the inner mitochondrial CC membrane with ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 CC complex, complex III, CIII). {ECO:0000250|UniProtKB:P00420}. CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane CC {ECO:0000250|UniProtKB:P00420}; Multi-pass membrane protein CC {ECO:0000250|UniProtKB:P00420}. CC -!- SIMILARITY: Belongs to the cytochrome c oxidase subunit 3 family. CC {ECO:0000305}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; M36270; AAA32065.2; -; Genomic_DNA. DR PIR; S07557; S07557. DR AlphaFoldDB; P14058; -. DR SMR; P14058; -. DR GO; GO:0005743; C:mitochondrial inner membrane; IEA:UniProtKB-SubCell. DR GO; GO:0004129; F:cytochrome-c oxidase activity; IEA:UniProtKB-EC. DR GO; GO:0019646; P:aerobic electron transport chain; IEA:InterPro. DR CDD; cd01665; Cyt_c_Oxidase_III; 1. DR Gene3D; 1.10.287.70; -; 1. DR Gene3D; 1.20.120.80; Cytochrome c oxidase, subunit III, four-helix bundle; 1. DR InterPro; IPR024791; Cyt_c/ubiquinol_Oxase_su3. DR InterPro; IPR033945; Cyt_c_oxase_su3_dom. DR InterPro; IPR000298; Cyt_c_oxidase-like_su3. DR InterPro; IPR035973; Cyt_c_oxidase_su3-like_sf. DR InterPro; IPR013833; Cyt_c_oxidase_su3_a-hlx. DR PANTHER; PTHR11403:SF7; CYTOCHROME C OXIDASE SUBUNIT 3; 1. DR PANTHER; PTHR11403; CYTOCHROME C OXIDASE SUBUNIT III; 1. DR Pfam; PF00510; COX3; 1. DR SUPFAM; SSF81452; Cytochrome c oxidase subunit III-like; 1. DR PROSITE; PS50253; COX3; 1. PE 3: Inferred from homology; KW Membrane; Mitochondrion; Mitochondrion inner membrane; Translocase; KW Transmembrane; Transmembrane helix. FT CHAIN 1..268 FT /note="Cytochrome c oxidase subunit 3" FT /id="PRO_0000183850" FT TRANSMEM 19..39 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 49..69 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 85..105 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 124..144 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 165..185 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 202..222 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 245..265 FT /note="Helical" FT /evidence="ECO:0000255" SQ SEQUENCE 268 AA; 29922 MW; B90B97B8DAE4265A CRC64; MTSIKFYQSF SAHLVQHSPW PILVSFSLFN LAIGTVLTMH GYSHSSTTFD LGLAVTVGSI LLWTRDIVIE GSFLGDHTKQ VQEGLIIGFI LFIISEVFAF ISVFWAYFHS ALSPAVELGS TWPPVGIIPL DTFSLPLFNT IILLSSGAFV TYGHHAIFSG KRLDSIIGLF LTVALALIFS YFQAFEYIHA GFSMSDSVFG TVFFASTGLH GIHVMLGTLF LFVSFLRQVN YQTTKEHNIG LETSILYWHF VDLVWLFLFL VVYFWGGA //