ID U5ZAB9_HUMAN Unreviewed; 261 AA. AC U5ZAB9; DT 22-JAN-2014, integrated into UniProtKB/TrEMBL. DT 22-JAN-2014, sequence version 1. DT 02-OCT-2024, entry version 36. DE RecName: Full=Cytochrome c oxidase subunit 3 {ECO:0000256|ARBA:ARBA00015944, ECO:0000256|RuleBase:RU003375}; GN Name=COX3 {ECO:0000313|EMBL:AHA02043.1}; OS Homo sapiens (Human). OG Mitochondrion {ECO:0000313|EMBL:AHA02043.1}. OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; OC Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; OC Homo. OX NCBI_TaxID=9606 {ECO:0000313|EMBL:AHA02043.1}; RN [1] {ECO:0000313|EMBL:AHA02043.1} RP NUCLEOTIDE SEQUENCE. RX PubMed=24349531; DOI=10.1371/journal.pone.0083570; RA Duggan A.T., Whitten M., Wiebe V., Crawford M., Butthof A., Spitsyn V., RA Makarov S., Novgorodov I., Osakovsky V., Pakendorf B.; RT "Investigating the Prehistory of Tungusic Peoples of Siberia and the Amur- RT Ussuri Region with Complete mtDNA Genome Sequences and Y-chromosomal RT Markers."; RL PLoS ONE 8:e83570-e83570(2013). 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:0000256|RuleBase:RU003375}. 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:0000256|ARBA:ARBA00029331}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:11437; CC Evidence={ECO:0000256|ARBA:ARBA00029331}; CC -!- SUBCELLULAR LOCATION: Membrane {ECO:0000256|ARBA:ARBA00004141}; Multi- CC pass membrane protein {ECO:0000256|ARBA:ARBA00004141}. CC -!- SIMILARITY: Belongs to the cytochrome c oxidase subunit 3 family. CC {ECO:0000256|ARBA:ARBA00010581, ECO:0000256|RuleBase:RU003375}. 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; KF148554; AHA02043.1; -; Genomic_DNA. DR AlphaFoldDB; U5ZAB9; -. DR PeptideAtlas; U5ZAB9; -. DR ChiTaRS; COX3; human. DR GO; GO:0016020; C:membrane; IEA:UniProtKB-SubCell. DR GO; GO:0005739; C:mitochondrion; IEA:UniProtKB-KW. 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 {ECO:0000256|ARBA:ARBA00023136, ECO:0000256|SAM:Phobius}; KW Mitochondrion {ECO:0000256|RuleBase:RU003375, ECO:0000313|EMBL:AHA02043.1}; KW Translocase {ECO:0000256|ARBA:ARBA00022967}; KW Transmembrane {ECO:0000256|ARBA:ARBA00022692, KW ECO:0000256|RuleBase:RU003375}; KW Transmembrane helix {ECO:0000256|ARBA:ARBA00022989, KW ECO:0000256|SAM:Phobius}. FT TRANSMEM 16..35 FT /note="Helical" FT /evidence="ECO:0000256|SAM:Phobius" FT TRANSMEM 41..58 FT /note="Helical" FT /evidence="ECO:0000256|SAM:Phobius" FT TRANSMEM 79..102 FT /note="Helical" FT /evidence="ECO:0000256|SAM:Phobius" FT TRANSMEM 159..177 FT /note="Helical" FT /evidence="ECO:0000256|SAM:Phobius" FT TRANSMEM 197..220 FT /note="Helical" FT /evidence="ECO:0000256|SAM:Phobius" FT TRANSMEM 240..260 FT /note="Helical" FT /evidence="ECO:0000256|SAM:Phobius" FT DOMAIN 4..261 FT /note="Heme-copper oxidase subunit III family profile" FT /evidence="ECO:0000259|PROSITE:PS50253" SQ SEQUENCE 261 AA; 29921 MW; A0438335DE21D914 CRC64; MTHQSHAYHM VKPSPWPLAG ALSALLMTSG LAMWFHFHSM TLLMLGLLTN TLTMYQWWRD VTRESTYQGH HTPPVQKGLR YGMILFITSE VFFFAGFFWA FYHSSLAPTP QLGGHWPPTG ITPLNPLEVP LLNTSVLLAS GVSITWAHHS LMENNRNQMI QALLITILLG LYFTLLQASE YFESPFTISD GIYGSTFFVA TGFHGLHVII GSTFLTICFI RQLMFHFTSK HHFGFEAAAW YWHFVDVVWL FLYVSIYWWG S //