CYB_LOXAA
ID CYB_LOXAA Reviewed; 378 AA.
AC B1B1W5;
DT 16-DEC-2008, integrated into UniProtKB/Swiss-Prot.
DT 29-APR-2008, sequence version 1.
DT 03-AUG-2022, entry version 61.
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:Cyt-b; Synonyms=Cob, cytb;
OS Loxocorone allax (Goblet worm) (Loxosomella allax).
OG Mitochondrion.
OC Eukaryota; Metazoa; Spiralia; Lophotrochozoa; Entoprocta; Loxosomatidae;
OC Loxocorone.
OX NCBI_TaxID=393181;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=18374604; DOI=10.1016/j.ympev.2008.02.013;
RA Yokobori S., Iseto T., Asakawa S., Sasaki T., Shimizu N., Yamagishi A.,
RA Oshima T., Hirose E.;
RT "Complete nucleotide sequences of mitochondrial genomes of two solitary
RT entoprocts, Loxocorone allax and Loxosomella aloxiata: Implications for
RT lophotrochozoan phylogeny.";
RL Mol. Phylogenet. Evol. 47:612-628(2008).
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:P00163}.
CC -!- COFACTOR:
CC Name=heme b; Xref=ChEBI:CHEBI:60344;
CC Evidence={ECO:0000250|UniProtKB:P00163};
CC Note=Binds 2 heme b groups non-covalently.
CC {ECO:0000250|UniProtKB:P00163};
CC -!- SUBUNIT: The main subunits of complex b-c1 are: cytochrome b,
CC cytochrome c1 and the Rieske protein. {ECO:0000250}.
CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane
CC {ECO:0000250|UniProtKB:P00163}; Multi-pass membrane protein
CC {ECO:0000250|UniProtKB:P00163}.
CC -!- SIMILARITY: Belongs to the cytochrome b family. {ECO:0000255|PROSITE-
CC ProRule:PRU00967, ECO:0000255|PROSITE-ProRule:PRU00968}.
CC -!- CAUTION: The protein contains an even number of transmembrane helices,
CC fewer than predicted by bioinformatics tools.
CC {ECO:0000250|UniProtKB:P00163}.
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DR EMBL; AB264799; BAG12580.1; -; Genomic_DNA.
DR RefSeq; YP_001718395.1; NC_010431.1.
DR AlphaFoldDB; B1B1W5; -.
DR SMR; B1B1W5; -.
DR GeneID; 6000140; -.
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..378
FT /note="Cytochrome b"
FT /id="PRO_0000357462"
FT TRANSMEM 34..54
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 78..100
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 113..133
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 179..199
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 225..245
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 289..306
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 313..342
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 350..369
FT /note="Helical"
FT /evidence="ECO:0000255"
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:P00163"
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:P00163"
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:P00163"
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:P00163"
FT BINDING 202
FT /ligand="a ubiquinone"
FT /ligand_id="ChEBI:CHEBI:16389"
FT /evidence="ECO:0000250|UniProtKB:P00157"
SQ SEQUENCE 378 AA; 43389 MW; 4A2E9C1E92229409 CRC64;
MYSPIRKSHP LLKMMSGSFS DLPSPSNFSI WWNFGSLLGL CLVIQILSGL FLSMHYTSHV
DLAFSSVAHI GRDVNYGWLL RSIHANGASF FFMCLYCHIG RGMYYMSYFF METWNVGVVI
FFLTMGTAFV GYVLPWGQMS FWGATVITNL ASAIPYIGEI LVQWVWGGFS VDNATLTRFF
SFHFLFPFMI AGLSMVHLLF LHQTGSNNPL GLNSDCDKIP FHWFYSTKDI AGFLVFFFVF
FIVVLLYPNG FTDPENFIPA NPLVTPVHIQ PEWYFLFAYA ILRSIPNKLG GVVSLVASIA
ILFCLPLTIS LMKFRSLVFY PLNQILFWSF CSIFLLLTWI GMRPVEDPYI FIGQILTVLY
FSYFLLNPLI LKFWDNLY
