CYB_AILME
ID CYB_AILME Reviewed; 379 AA.
AC Q33784; A5JFK8;
DT 15-MAR-2005, integrated into UniProtKB/Swiss-Prot.
DT 14-MAY-2014, sequence version 2.
DT 03-AUG-2022, entry version 110.
DE RecName: Full=Cytochrome b;
DE AltName: Full=Complex III subunit 3;
DE AltName: Full=Complex III subunit III;
DE AltName: Full=Cytochrome b-c1 complex subunit 3;
DE AltName: Full=Ubiquinol-cytochrome-c reductase complex cytochrome b subunit;
GN Name=MT-CYB; Synonyms=COB, CYTB, MTCYB;
OS Ailuropoda melanoleuca (Giant panda).
OG Mitochondrion.
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Laurasiatheria; Carnivora; Caniformia; Ursidae; Ailuropoda.
OX NCBI_TaxID=9646;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=8744769; DOI=10.1006/mpev.1996.0051;
RA Talbot S.L., Shields G.F.;
RT "A phylogeny of the bears (Ursidae) inferred from complete sequences of
RT three mitochondrial genes.";
RL Mol. Phylogenet. Evol. 5:567-575(1996).
RN [2]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RX PubMed=17499457; DOI=10.1016/j.gene.2007.04.009;
RA Peng R., Zeng B., Meng X., Yue B., Zhang Z., Zou F.;
RT "The complete mitochondrial genome and phylogenetic analysis of the giant
RT panda (Ailuropoda melanoleuca).";
RL Gene 397:76-83(2007).
CC -!- FUNCTION: Component of the ubiquinol-cytochrome c reductase complex
CC (complex III or cytochrome b-c1 complex) that is part of the
CC mitochondrial respiratory chain. The b-c1 complex mediates electron
CC transfer from ubiquinol to cytochrome c. Contributes to the generation
CC of a proton gradient across the mitochondrial membrane that is then
CC used for ATP synthesis. {ECO:0000250|UniProtKB:P00157}.
CC -!- COFACTOR:
CC Name=heme b; Xref=ChEBI:CHEBI:60344;
CC Evidence={ECO:0000250|UniProtKB:P00157};
CC Note=Binds 2 heme b groups non-covalently.
CC {ECO:0000250|UniProtKB:P00157};
CC -!- SUBUNIT: The cytochrome bc1 complex contains 11 subunits: 3 respiratory
CC subunits (MT-CYB, CYC1 and UQCRFS1), 2 core proteins (UQCRC1 and
CC UQCRC2) and 6 low-molecular weight proteins (UQCRH/QCR6, UQCRB/QCR7,
CC UQCRQ/QCR8, UQCR10/QCR9, UQCR11/QCR10 and a cleavage product of
CC UQCRFS1). This cytochrome bc1 complex then forms a dimer.
CC {ECO:0000250|UniProtKB:P00157}.
CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane
CC {ECO:0000250|UniProtKB:P00157}; Multi-pass membrane protein
CC {ECO:0000250|UniProtKB:P00157}.
CC -!- MISCELLANEOUS: Heme 1 (or BL or b562) is low-potential and absorbs at
CC about 562 nm, and heme 2 (or BH or b566) is high-potential and absorbs
CC at about 566 nm. {ECO:0000250}.
CC -!- SIMILARITY: Belongs to the cytochrome b family. {ECO:0000255|PROSITE-
CC ProRule:PRU00967, ECO:0000255|PROSITE-ProRule:PRU00968}.
CC -!- CAUTION: The full-length protein contains only eight transmembrane
CC helices, not nine as predicted by bioinformatics tools.
CC {ECO:0000250|UniProtKB:P00157}.
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; U23552; AAB50498.1; -; Genomic_DNA.
DR EMBL; EF212882; ABP38222.1; -; Genomic_DNA.
DR RefSeq; YP_001249296.1; NC_009492.1.
DR AlphaFoldDB; Q33784; -.
DR SMR; Q33784; -.
DR STRING; 9646.ENSAMEP00000021365; -.
DR GeneID; 5179733; -.
DR KEGG; aml:5179733; -.
DR CTD; 4519; -.
DR eggNOG; KOG4663; Eukaryota.
DR HOGENOM; CLU_031114_3_0_1; -.
DR InParanoid; Q33784; -.
DR OMA; RFFAFHF; -.
DR OrthoDB; 1125966at2759; -.
DR TreeFam; TF353088; -.
DR Proteomes; UP000008912; Mitochondrion.
DR GO; GO:0005743; C:mitochondrial inner membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0045275; C:respiratory chain complex III; IEA:InterPro.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0008121; F:ubiquinol-cytochrome-c reductase activity; IEA:InterPro.
DR GO; GO:0022904; P:respiratory electron transport chain; IEA:InterPro.
DR CDD; cd00290; cytochrome_b_C; 1.
DR CDD; cd00284; Cytochrome_b_N; 1.
DR Gene3D; 1.20.810.10; -; 1.
DR InterPro; IPR005798; Cyt_b/b6_C.
DR InterPro; IPR036150; Cyt_b/b6_C_sf.
DR InterPro; IPR005797; Cyt_b/b6_N.
DR InterPro; IPR027387; Cytb/b6-like_sf.
DR InterPro; IPR030689; Cytochrome_b.
DR InterPro; IPR016174; Di-haem_cyt_TM.
DR Pfam; PF00032; Cytochrom_B_C; 1.
DR Pfam; PF00033; Cytochrome_B; 1.
DR PIRSF; PIRSF038885; COB; 1.
DR SUPFAM; SSF81342; SSF81342; 1.
DR SUPFAM; SSF81648; SSF81648; 1.
DR PROSITE; PS51003; CYTB_CTER; 1.
DR PROSITE; PS51002; CYTB_NTER; 1.
PE 3: Inferred from homology;
KW Electron transport; Heme; Iron; Membrane; Metal-binding; Mitochondrion;
KW Mitochondrion inner membrane; Reference proteome; Respiratory chain;
KW Transmembrane; Transmembrane helix; Transport; Ubiquinone.
FT CHAIN 1..379
FT /note="Cytochrome b"
FT /id="PRO_0000060538"
FT TRANSMEM 33..53
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 77..98
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 113..133
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 178..198
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 226..246
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 288..308
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 320..340
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 347..367
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT BINDING 83
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="b562"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT BINDING 97
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="b566"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT BINDING 182
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="b562"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT BINDING 196
FT /ligand="heme b"
FT /ligand_id="ChEBI:CHEBI:60344"
FT /ligand_label="b566"
FT /ligand_part="Fe"
FT /ligand_part_id="ChEBI:CHEBI:18248"
FT /note="axial binding residue"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT BINDING 201
FT /ligand="a ubiquinone"
FT /ligand_id="ChEBI:CHEBI:16389"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT CONFLICT 123
FT /note="V -> I (in Ref. 1; AAB50498)"
FT /evidence="ECO:0000305"
FT CONFLICT 164
FT /note="V -> I (in Ref. 1; AAB50498)"
FT /evidence="ECO:0000305"
FT CONFLICT 264
FT /note="A -> T (in Ref. 1; AAB50498)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 379 AA; 42645 MW; 8A51D8E8EDBBA5BA CRC64;
MINIRKTHPL VKIINNSFID LPTPSNISTW WNFGSLLGVC LILQILTGLF LAMHYTSDTA
TAFSSVAHIC RDVNYGWFIR YMHANGASMF FICLFMHVGR GLYYGSYLFP ETWNIGIILL
LTVMATAFMG YVLPWGQMSF WGATVITNLL SAIPYIGTNL VEWVWGGFSV DKATLTRFFA
FHFILPFIIS ALAMVHLLFL HETGSNNPSG IPSDPDKIPF YPYHTIKDIL GVLFLVLALM
TLALFSPDLL GDPDNYTPAN PLSAPPHIKP EWYFLFAYAI LRSIPNKLGG VLALIFSILI
LTIIPLLHTS KQRSMMFRPL SQCLFWLLVA DLLTLTWIGG QPVEHPFIII GQLASILYFT
ILLVLMPITS IIENSLSKW
