ID COX3_KLULA Reviewed; 269 AA. AC Q9XLW9; Q6DN55; DT 27-SEP-2004, integrated into UniProtKB/Swiss-Prot. DT 11-OCT-2004, sequence version 2. DT 08-NOV-2023, entry version 112. DE RecName: Full=Cytochrome c oxidase subunit 3; DE EC=7.1.1.9; DE AltName: Full=Cytochrome c oxidase polypeptide III; GN Name=COX3; OS Kluyveromyces lactis (strain ATCC 8585 / CBS 2359 / DSM 70799 / NBRC 1267 / OS NRRL Y-1140 / WM37) (Yeast) (Candida sphaerica). OG Mitochondrion. OC Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; Saccharomycetes; OC Saccharomycetales; Saccharomycetaceae; Kluyveromyces. OX NCBI_TaxID=284590; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RC STRAIN=ATCC 8585 / CBS 2359 / DSM 70799 / NBRC 1267 / NRRL Y-1140 / RC WM37; RX PubMed=10757749; DOI=10.1093/genetics/154.3.999; RA Costanzo M.C., Bonnefoy N., Williams E.H., Clark-Walker G.D., Fox T.D.; RT "Highly diverged homologs of Saccharomyces cerevisiae mitochondrial mRNA- RT specific translational activators have orthologous functions in other RT budding yeasts."; RL Genetics 154:999-1012(2000). RN [2] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=ATCC 76492 / CBS 2359/152 / CLIB 210; RX PubMed=15691736; DOI=10.1016/j.femsyr.2004.09.003; RA Zivanovic Y., Wincker P., Vacherie B., Bolotin-Fukuhara M., Fukuhara H.; RT "Complete nucleotide sequence of the mitochondrial DNA from Kluyveromyces RT lactis."; RL FEMS Yeast Res. 5:315-322(2005). 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; AF120716; AAD29123.1; -; Genomic_DNA. DR EMBL; AY654900; AAT64954.1; -; Genomic_DNA. DR RefSeq; YP_054504.1; NC_006077.1. DR AlphaFoldDB; Q9XLW9; -. DR SMR; Q9XLW9; -. DR STRING; 284590.Q9XLW9; -. DR PaxDb; 284590-Q9XLW9; -. DR GeneID; 2914070; -. DR KEGG; kla:KllafMp08; -. DR InParanoid; Q9XLW9; -. 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..269 FT /note="Cytochrome c oxidase subunit 3" FT /id="PRO_0000183795" FT TRANSMEM 21..41 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 45..65 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 90..110 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 138..160 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 167..187 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 205..225 FT /note="Helical" FT /evidence="ECO:0000255" FT TRANSMEM 247..267 FT /note="Helical" FT /evidence="ECO:0000255" FT CONFLICT 32 FT /note="S -> A (in Ref. 1; AAD29123)" FT /evidence="ECO:0000305" SQ SEQUENCE 269 AA; 30432 MW; 77DC8D1DE2A20C8F CRC64; MTHLERSRHQ QFPFHLVAPS PWPIVVSFAL MSLALSLALT MHGYIGHMYL IYLSILTVTL SATLWFRDII AEATYLGDHT IAVRKGINLG FLLFVVSEIL IFAALFWAYF HSAMSPNIEL GGVWPPVGIQ AVQPTELPLL NTIILLSSGA TITYSHHGLV GGNRKNALSG LLITFWLIVI FVTCQYIEYT NATFTITDGV YGSVFYAGTG LHFLHMVMLA AMLGINYWRL RNYHLTATHH VGYETTVLYC HILDIIWLFL YIVFYWWGV //