CYB_LITCT
ID CYB_LITCT Reviewed; 380 AA.
AC P16674; Q9T6R7;
DT 01-AUG-1990, integrated into UniProtKB/Swiss-Prot.
DT 23-APR-2003, sequence version 2.
DT 03-AUG-2022, entry version 103.
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 Lithobates catesbeianus (American bullfrog) (Rana catesbeiana).
OG Mitochondrion.
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Amphibia;
OC Batrachia; Anura; Neobatrachia; Ranoidea; Ranidae; Lithobates.
OX NCBI_TaxID=8400;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA Lee J.-E., Lee H.-Y., Yang S.-Y.;
RT "Genetic relationships of mitochondrial cytochrome b gene among six Korean
RT Rana species.";
RL Submitted (NOV-1999) to the EMBL/GenBank/DDBJ databases.
RN [2]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 267-380.
RX PubMed=2444617; DOI=10.1272/jnms1923.54.429;
RA Yoneyama Y.;
RT "The nucleotide sequences of the heavy and light strand replication origins
RT of the Rana catesbeiana mitochondrial genome.";
RL Nippon Ika Daigaku Zasshi 54:429-440(1987).
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 3 respiratory subunits
CC (MT-CYB, CYC1 and UQCRFS1), 2 core proteins (UQCRC1 and UQCRC2) and
CC probably 6 low-molecular weight proteins.
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; AF205089; AAF17088.1; -; Genomic_DNA.
DR EMBL; D12694; BAA02191.1; -; Genomic_DNA.
DR AlphaFoldDB; P16674; -.
DR SMR; P16674; -.
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_0000061482"
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 CONFLICT 297
FT /note="L -> F (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 300..301
FT /note="MV -> LI (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 304
FT /note="R -> L (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 324
FT /note="T -> I (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 328
FT /note="A -> T (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 344
FT /note="G -> V (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 350
FT /note="T -> I (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 355
FT /note="A -> T (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 369
FT /note="S -> T (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
FT CONFLICT 380
FT /note="I -> V (in Ref. 2; BAA02191)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 380 AA; 42345 MW; DB7C4A7252D135C9 CRC64;
MAPTMRKSHP LLKIINGSFI DLPSPANLWA WWNFGSLLGV CLVAQIVTGL FLAMHYTADT
SLAFSSIAHI CRDVNNGWLL RNLHANGASF FFICIYFHIG RGLYYGSYLY KETWNIGVIL
LFLVMATAFV GYVLPWGQMS FWGATVITNL LSAAPYIGSD LVQWIWGGFS VDNATLTRFF
TFHFILPFII AAASMIHLLF LHQTGSSNPT GLNSNLDKVS FHPYFSYKDL FGFVIMLGAL
ASLSTFAPNL LGDPDNFTPA NPLVTPPHIK PEWYFLFAYA ILRSIPNKLG GVLALLLSIM
VLFRMPIIHT SKLRSLMFRP IAKTFFWALI ANTAILTWIG GQPGEDPFIT IGQIASGLYF
LIFVLLIPSL GLLENKLLKI
