CYB_KLULA
ID CYB_KLULA Reviewed; 386 AA.
AC P81381; Q6DN62;
DT 15-NOV-2002, integrated into UniProtKB/Swiss-Prot.
DT 11-OCT-2004, sequence version 2.
DT 03-AUG-2022, entry version 127.
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=COB; Synonyms=CYTB;
OS Kluyveromyces lactis (strain ATCC 8585 / CBS 2359 / DSM 70799 / NBRC 1267 /
OS NRRL Y-1140 / WM37) (Yeast) (Candida sphaerica).
OG Mitochondrion.
OC Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; Saccharomycetes;
OC Saccharomycetales; Saccharomycetaceae; Kluyveromyces.
OX NCBI_TaxID=284590;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC STRAIN=ATCC 8585 / CBS 2359 / DSM 70799 / NBRC 1267 / NRRL Y-1140 / WM37,
RC and WM27 / NRRL Y-17066;
RX PubMed=2735138; DOI=10.1002/yea.320050310;
RA Brunner A., Coria R.;
RT "Cloning and sequencing of the gene for apocytochrome b of the yeast
RT Kluyveromyces lactis strains WM27 (NRRL Y-17066) and WM37 (NRRL Y-1140).";
RL Yeast 5:209-218(1989).
RN [2]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=ATCC 76492 / CBS 2359/152 / CLIB 210;
RX PubMed=15691736; DOI=10.1016/j.femsyr.2004.09.003;
RA Zivanovic Y., Wincker P., Vacherie B., Bolotin-Fukuhara M., Fukuhara H.;
RT "Complete nucleotide sequence of the mitochondrial DNA from Kluyveromyces
RT lactis.";
RL FEMS Yeast Res. 5:315-322(2005).
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: Fungal cytochrome b-c1 complex contains 10 subunits; 3
CC respiratory subunits, 2 core proteins and 5 low-molecular weight
CC proteins. Cytochrome b-c1 complex is a homodimer.
CC {ECO:0000250|UniProtKB:P00163}.
CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane
CC {ECO:0000250|UniProtKB:P00163}; Multi-pass membrane protein
CC {ECO:0000250|UniProtKB:P00163}.
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 protein contains only eight transmembrane helices, not
CC nine as predicted by bioinformatics tools.
CC {ECO:0000250|UniProtKB:P00163}.
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DR EMBL; AY654900; AAT64950.1; -; Genomic_DNA.
DR PIR; S12352; S12352.
DR RefSeq; YP_054497.1; NC_006077.1.
DR AlphaFoldDB; P81381; -.
DR SMR; P81381; -.
DR STRING; 284590.P81381; -.
DR GeneID; 2914051; -.
DR KEGG; kla:KllafMp02; -.
DR InParanoid; P81381; -.
DR Proteomes; UP000000598; 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..386
FT /note="Cytochrome b"
FT /id="PRO_0000061745"
FT TRANSMEM 32..52
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 76..98
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..309
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 321..341
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT TRANSMEM 348..368
FT /note="Helical"
FT /evidence="ECO:0000250|UniProtKB:P00163"
FT BINDING 82
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:0000255|PROSITE-ProRule:PRU00968"
FT BINDING 96
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:0000255|PROSITE-ProRule:PRU00968"
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:0000255|PROSITE-ProRule:PRU00968"
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:0000255|PROSITE-ProRule:PRU00968"
FT BINDING 202
FT /ligand="a ubiquinone"
FT /ligand_id="ChEBI:CHEBI:16389"
FT /evidence="ECO:0000250|UniProtKB:P00157"
FT CONFLICT 385
FT /note="A -> T (in Ref. 1; no nucleotide entry)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 386 AA; 43623 MW; 56CBA2D8611478F4 CRC64;
MSFRKSNIYL NLLNSYMIDS PQPSSINYWW NLGSLLGLCL VIQICTGIFL AMHYSSNIEL
AFSAVEHIMR DVQGGWFIRY AHANGASFFF ICMYIHIGKG LYYGSYRAPR TLVWNVGVII
FVLTMAAAFL GYCCVYGQMS HWGATVITNL FSAIPFIGND IVSWLWGGFS VSNPTIQRFF
AFHYLVPFII AAFVIMHFMA LHTHGSSNPL GVTGNLDRLP MHGYFIFKDL ITVFVFLFFF
SLFVFFSPNT MGHPDNYIPG NPLVTPASIV PEWYLLPFYA ILRSVPDKLL GVLAMFGAIL
ILLVLPITDR SVIRGNAFKV FSKFFFFLFI ANFVLLGHLG ECHVEPPFVV MGQIATVIYF
AYFLVIVPVV STIENVLFYV GRKNAK
