CYB_APUAP
ID CYB_APUAP Reviewed; 380 AA.
AC Q33629; Q33630; Q8HF68;
DT 15-JUL-1998, integrated into UniProtKB/Swiss-Prot.
DT 23-APR-2003, sequence version 2.
DT 03-AUG-2022, entry version 107.
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 Apus apus (Common swift).
OG Mitochondrion.
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC Archelosauria; Archosauria; Dinosauria; Saurischia; Theropoda;
OC Coelurosauria; Aves; Neognathae; Caprimulgimorphae; Apodiformes; Apodidae;
OC Apodinae; Apus.
OX NCBI_TaxID=8895;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC STRAIN=Isolate A1;
RX PubMed=12967609; DOI=10.1016/s1055-7903(03)00066-6;
RA Thomassen H.A., Wiersema A.T., de Bakker M.A.G., de Knijff P., Hetebrij E.,
RA Povel G.D.E.;
RT "A new phylogeny of swiftlets (Aves: Apodidae) based on cytochrome-b DNA.";
RL Mol. Phylogenet. Evol. 29:86-93(2003).
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 138-272.
RC STRAIN=Isolate PL02, and Isolate PL05;
RX PubMed=8692950; DOI=10.1073/pnas.93.14.7091;
RA Lee P.L.M., Clayton D.H., Griffiths R., Page R.D.;
RT "Does behavior reflect phylogeny in swiftlets (Aves: Apodidae)? A test
RT using cytochrome b mitochondrial DNA sequences.";
RL Proc. Natl. Acad. Sci. U.S.A. 93:7091-7096(1996).
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; AY135633; AAN39915.1; -; Genomic_DNA.
DR EMBL; U49981; AAC59940.1; -; Genomic_DNA.
DR EMBL; U49982; AAC59941.1; -; Genomic_DNA.
DR RefSeq; YP_829500.1; NC_008540.1.
DR AlphaFoldDB; Q33629; -.
DR SMR; Q33629; -.
DR GeneID; 4443263; -.
DR CTD; 4519; -.
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; Respiratory chain; Transmembrane;
KW Transmembrane helix; Transport; Ubiquinone.
FT CHAIN 1..380
FT /note="Cytochrome b"
FT /id="PRO_0000060613"
FT TRANSMEM 34..54
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 78..99
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 114..134
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 179..199
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 227..247
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 289..309
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 321..341
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT TRANSMEM 348..368
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT BINDING 84
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 98
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 183
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 197
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 202
FT /ligand="a ubiquinone"
FT /ligand_id="ChEBI:CHEBI:16389"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT VARIANT 198
FT /note="L -> P (in strain: Isolate PL05)"
FT CONFLICT 163
FT /note="E -> Q (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
FT CONFLICT 172
FT /note="D -> G (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
FT CONFLICT 212
FT /note="V -> I (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
FT CONFLICT 226
FT /note="S -> A (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
FT CONFLICT 230
FT /note="L -> P (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
FT CONFLICT 237
FT /note="L -> F (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
FT CONFLICT 241
FT /note="L -> M (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
FT CONFLICT 253
FT /note="D -> G (in Ref. 2; AAC59940/AAC59941)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 380 AA; 42554 MW; CFA67D7F6659EB46 CRC64;
MAPNPRKSHP LLKMVNNSLI DLPTPPNISA WWNFGSLLGI CLATQIITGL LLAMHYTADT
TLAFSSVAHT CRNVQYGWLI RNLHANGASF FFICIYLHIG RGFYYGSYLY KETWNTGVIL
LLTLMATAFV GYVLPWGQMS FWGATVITNL FSAIPYIGQT LVEWAWGGFS VDNPTLTRFF
ALHFLLPFLI AGLTLIHLTF LHESGSNNPL GVVSNCDKIP FHPYFSTKDL LGFIIMLTPL
LTLALFSPNL LGDPENFTPA NPLVTPPHIK PEWYFLFAYA ILRSIPNKLG GVLALAASVL
ILFLCPFLHK SKQRTMTFRP LSQILFWVLV ANLLILTWVG SQPVEHPFII IGQLASLTYF
TILLILFPLI GALENKMLNY
