COX3_HETBL
ID COX3_HETBL Reviewed; 259 AA.
AC O47475;
DT 01-DEC-2000, integrated into UniProtKB/Swiss-Prot.
DT 01-JUN-1998, sequence version 1.
DT 25-MAY-2022, entry version 98.
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 Heterololigo bleekeri (Spear squid) (Loligo bleekeri).
OG Mitochondrion.
OC Eukaryota; Metazoa; Spiralia; Lophotrochozoa; Mollusca; Cephalopoda;
OC Coleoidea; Decapodiformes; Teuthida; Myopsina; Loliginidae; Heterololigo.
OX NCBI_TaxID=1423826;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA Tomita K., Ueda T., Watanabe K.;
RT "Completing of squid (Loligo breekeri) mitochondrial genome sequencing.";
RL Submitted (DEC-1997) 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: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}.
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DR EMBL; AB009838; BAA24058.1; -; Genomic_DNA.
DR EMBL; AB029616; BAB03645.1; -; Genomic_DNA.
DR RefSeq; NP_062833.1; NC_002507.1.
DR AlphaFoldDB; O47475; -.
DR SMR; O47475; -.
DR GeneID; 809435; -.
DR CTD; 4514; -.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
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; 1.20.120.80; -; 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; PTHR11403; 1.
DR Pfam; PF00510; COX3; 1.
DR SUPFAM; SSF81452; SSF81452; 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..259
FT /note="Cytochrome c oxidase subunit 3"
FT /id="PRO_0000183801"
FT TRANSMEM 13..33
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 36..56
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 80..100
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 125..145
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 154..174
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 195..215
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 237..257
FT /note="Helical"
FT /evidence="ECO:0000255"
SQ SEQUENCE 259 AA; 29637 MW; 10B61CB81E5ACA41 CRC64;
MIRNPFHLVE YSPWPLTGSL GAMFLTVGLT SWFHNHGFIT MLLGLFLVLM TMFQWWRDII
RESTFQGYHT MKVSLGMRMG MVLFITSEIC FFFAFFWAYF HSSLAPNTDI GASWPPLHIN
PLNPFQIPLL NTAILLASGV TVTWAHHSLM GGNHAEATQS MVLTVILGGY FTLLQAEEYM
EAPFSIADSV YGATFFVATG FHGLHVIIGS VFLLICLFRM LIHHFSTNHH FGFEAAAWYW
HFVDVVWLIL YTCIYWWGS
