ID   COX2_CULQU              Reviewed;         228 AA.
AC   P50693; A7LGN8; Q9B813;
DT   01-OCT-1996, integrated into UniProtKB/Swiss-Prot.
DT   01-OCT-1996, sequence version 1.
DT   24-JAN-2024, entry version 120.
DE   RecName: Full=Cytochrome c oxidase subunit 2;
DE            EC=7.1.1.9;
DE   AltName: Full=Cytochrome c oxidase polypeptide II;
GN   Name=COII; Synonyms=CO2;
OS   Culex quinquefasciatus (Southern house mosquito) (Culex pungens).
OG   Mitochondrion.
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Hexapoda; Insecta; Pterygota;
OC   Neoptera; Endopterygota; Diptera; Nematocera; Culicoidea; Culicidae;
OC   Culicinae; Culicini; Culex; Culex.
OX   NCBI_TaxID=7176;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC   STRAIN=Yi-lan; TISSUE=Larva;
RX   PubMed=7608924; DOI=10.1093/jmedent/32.2.174;
RA   Ho C.M., Liu Y.M., Wei Y.H., Hu S.T.;
RT   "Gene for cytochrome c oxidase subunit II in the mitochondrial DNA of Culex
RT   quinquefasciatus and Aedes aegypti (Diptera: Culicidae).";
RL   J. Med. Entomol. 32:174-180(1995).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA   Wang J., Huang C.;
RT   "Molecular evolution of the mitochondrial cytochrome oxidase II gene in
RT   three mosquitoes.";
RL   Submitted (DEC-2000) to the EMBL/GenBank/DDBJ databases.
RN   [3]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA   Hasan A.U., Suguri S., Abedin S.M., Fujimoto C., Itaki R., Harada M.,
RA   Zaman R.U., Al Mamun M.A., Rahman M.A.;
RT   "Phylogenetic relationships of some common Culex mosquitoes of Bangladesh
RT   based on nuclear and mitochondrial DNA.";
RL   Submitted (JUL-2007) to the EMBL/GenBank/DDBJ databases.
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:P00410}.
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:P00410};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:11437;
CC         Evidence={ECO:0000250|UniProtKB:P00410};
CC   -!- COFACTOR:
CC       Name=Cu cation; Xref=ChEBI:CHEBI:23378;
CC         Evidence={ECO:0000250|UniProtKB:P00410};
CC       Note=Binds a dinuclear copper A center per subunit.
CC       {ECO:0000250|UniProtKB:P00410};
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:P00410}.
CC   -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane
CC       {ECO:0000250|UniProtKB:P00410}; Multi-pass membrane protein
CC       {ECO:0000250|UniProtKB:P00410}.
CC   -!- SIMILARITY: Belongs to the cytochrome c oxidase subunit 2 family.
CC       {ECO:0000305}.
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DR   EMBL; L34351; AAA79167.1; -; Genomic_DNA.
DR   EMBL; AF325716; AAK14328.1; -; Genomic_DNA.
DR   EMBL; EU014281; ABS52760.1; -; Genomic_DNA.
DR   EMBL; EU014282; ABS52761.1; -; Genomic_DNA.
DR   AlphaFoldDB; P50693; -.
DR   SMR; P50693; -.
DR   VEuPathDB; VectorBase:CPIJ040080; -.
DR   VEuPathDB; VectorBase:CQUJHB006026; -.
DR   eggNOG; KOG4767; Eukaryota.
DR   HOGENOM; CLU_036876_2_3_1; -.
DR   InParanoid; P50693; -.
DR   Proteomes; UP000002320; Unplaced.
DR   GO; GO:0005743; C:mitochondrial inner membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0070469; C:respirasome; IEA:UniProtKB-KW.
DR   GO; GO:0005507; F:copper ion binding; IEA:InterPro.
DR   GO; GO:0004129; F:cytochrome-c oxidase activity; IEA:UniProtKB-EC.
DR   CDD; cd13912; CcO_II_C; 1.
DR   Gene3D; 1.10.287.90; -; 1.
DR   Gene3D; 2.60.40.420; Cupredoxins - blue copper proteins; 1.
DR   InterPro; IPR045187; CcO_II.
DR   InterPro; IPR002429; CcO_II-like_C.
DR   InterPro; IPR034210; CcO_II_C.
DR   InterPro; IPR001505; Copper_CuA.
DR   InterPro; IPR008972; Cupredoxin.
DR   InterPro; IPR014222; Cyt_c_oxidase_su2.
DR   InterPro; IPR011759; Cyt_c_oxidase_su2_TM_dom.
DR   InterPro; IPR036257; Cyt_c_oxidase_su2_TM_sf.
DR   NCBIfam; TIGR02866; CoxB; 1.
DR   PANTHER; PTHR22888:SF9; CYTOCHROME C OXIDASE SUBUNIT 2; 1.
DR   PANTHER; PTHR22888; CYTOCHROME C OXIDASE, SUBUNIT II; 1.
DR   Pfam; PF00116; COX2; 1.
DR   Pfam; PF02790; COX2_TM; 1.
DR   PRINTS; PR01166; CYCOXIDASEII.
DR   SUPFAM; SSF49503; Cupredoxins; 1.
DR   SUPFAM; SSF81464; Cytochrome c oxidase subunit II-like, transmembrane region; 1.
DR   PROSITE; PS00078; COX2; 1.
DR   PROSITE; PS50857; COX2_CUA; 1.
DR   PROSITE; PS50999; COX2_TM; 1.
PE   3: Inferred from homology;
KW   Copper; Electron transport; Magnesium; Membrane; Metal-binding;
KW   Mitochondrion; Mitochondrion inner membrane; Reference proteome;
KW   Respiratory chain; Translocase; Transmembrane; Transmembrane helix;
KW   Transport.
FT   CHAIN           1..228
FT                   /note="Cytochrome c oxidase subunit 2"
FT                   /id="PRO_0000183561"
FT   TOPO_DOM        1..26
FT                   /note="Mitochondrial intermembrane"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        27..48
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        49..62
FT                   /note="Mitochondrial matrix"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        63..82
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        83..228
FT                   /note="Mitochondrial intermembrane"
FT                   /evidence="ECO:0000255"
FT   BINDING         161
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A1"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         196
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A1"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         196
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A2"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         198
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A2"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         198
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_note="ligand shared with subunit 1"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         200
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A1"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         200
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A2"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         204
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A2"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   BINDING         207
FT                   /ligand="Cu cation"
FT                   /ligand_id="ChEBI:CHEBI:23378"
FT                   /ligand_label="A1"
FT                   /evidence="ECO:0000250|UniProtKB:P00410"
FT   CONFLICT        8
FT                   /note="G -> W (in Ref. 2; AAK14328)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        135
FT                   /note="L -> S (in Ref. 2; AAK14328)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   228 AA;  26319 MW;  49B58BDA434D4CAB CRC64;
     MATWANLGLQ NSSSPLMEQL NFFHDHTVLI LIMITVMITY VMGMLFFNKF TNRYLLHGQT
     IEIIWTILPA IILMFIAFPS LRLLYLLDEI NSPLITLKAI GHQWYWSYEY SNFMNLEFDS
     YMIPTNELDL NGFRLLDVDN RIILPLNNQI RILVTATDVL HSWTVPSLGV KIDATPGRLN
     QTNFLINQSG LFFGQCSEIC GANHSFMPIV IESIPMNYFI KWVSSQLN
//