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I3Q5S1 · I3Q5S1_HUMAN

Function

function

Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex) that is part of the mitochondrial respiratory chain. The b-c1 complex mediates electron transfer from ubiquinol to cytochrome c. Contributes to the generation of a proton gradient across the mitochondrial membrane that is then used for ATP synthesis.

Cofactor

Protein has several cofactor binding sites:
heme b (UniProtKB | Rhea| CHEBI:60344 )

Note: Binds 2 heme groups non-covalently.
heme (UniProtKB | Rhea| CHEBI:30413 )

Note: Binds 2 heme groups non-covalently.

Features

Showing features for binding site.

138050100150200250300350
TypeIDPosition(s)Description
Binding site83Fe (UniProtKB | ChEBI) of heme b b562 (UniProtKB | ChEBI); axial binding residue
Binding site97Fe (UniProtKB | ChEBI) of heme b b566 (UniProtKB | ChEBI); axial binding residue
Binding site182Fe (UniProtKB | ChEBI) of heme b b562 (UniProtKB | ChEBI); axial binding residue
Binding site196Fe (UniProtKB | ChEBI) of heme b b566 (UniProtKB | ChEBI); axial binding residue
Binding site201a ubiquinone (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentmitochondrial inner membrane
Cellular Componentrespiratory chain complex III
Molecular Functionmetal ion binding
Molecular Functionubiquinol-cytochrome-c reductase activity
Biological Processrespiratory electron transport chain

Keywords

Names & Taxonomy

Protein names

  • Recommended name
    Cytochrome b

Gene names

    • Name
      CYTB

Encoded on

  • Mitochondrion

Organism names

  • Taxonomic identifier
  • Organism
  • Taxonomic lineage
    Eukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo

Accessions

  • Primary accession
    I3Q5S1

Subcellular Location

Features

Showing features for transmembrane.

TypeIDPosition(s)Description
Transmembrane30-56Helical
Transmembrane77-98Helical
Transmembrane113-133Helical
Transmembrane140-158Helical
Transmembrane178-200Helical
Transmembrane229-246Helical
Transmembrane288-308Helical
Transmembrane320-339Helical
Transmembrane345-372Helical

Keywords

PTM/Processing

Proteomic databases

Interaction

Subunit

The cytochrome bc1 complex contains 11 subunits: 3 respiratory subunits (MT-CYB, CYC1 and UQCRFS1), 2 core proteins (UQCRC1 and UQCRC2) and 6 low-molecular weight proteins (UQCRH/QCR6, UQCRB/QCR7, UQCRQ/QCR8, UQCR10/QCR9, UQCR11/QCR10 and a cleavage product of UQCRFS1). This cytochrome bc1 complex then forms a dimer.

Family & Domains

Features

Showing features for domain.

TypeIDPosition(s)Description
Domain1-209Cytochrome b/b6 N-terminal region profile
Domain210-380Cytochrome b/b6 C-terminal region profile

Sequence similarities

Belongs to the cytochrome b family.

Keywords

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    380
  • Mass (Da)
    42,730
  • Last updated
    2012-09-05 v1
  • MD5 Checksum
    20DAFB08BDE62F8AB1431BE16DC5F1E0
MTPMRKINPLMKLINHSFIDLPTPSNISAWWNFGSLLGACLILQITTGLFLAMHYSPDASTAFSSIAHITRDVNYGWIIRYLHANGASMFFICLFLHIGRGLYYGSFLYSETWNIGIILLLATMATAFMGYVLPWGQMSFWGATVITNLLSAIPYIGTDLVQWIWGGYSVDSPTLTRFFTFHFILPFIIAALTALHLLFLHETGSNNPLGITSHSDKITFHPYYTIKDALGLLLFILSLMTLTLFSPDLLGDPDNYTLANPLNTPPHIKPEWYFLFAYTILRSVPNKLGGVLALLLSILILAMIPILHMSKQQSMMFRPLSQSLYWLLAADLLILTWIGGQPVSYPFTIIGQVASVLYFTTILILMPTISLIENKMLKWA

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
JQ797991
EMBL· GenBank· DDBJ
AFI52643.1
EMBL· GenBank· DDBJ
Genomic DNA
KM213520
EMBL· GenBank· DDBJ
AIG52451.1
EMBL· GenBank· DDBJ
Genomic DNA
KJ801401
EMBL· GenBank· DDBJ
AIL91083.1
EMBL· GenBank· DDBJ
Genomic DNA
KJ801402
EMBL· GenBank· DDBJ
AIL91096.1
EMBL· GenBank· DDBJ
Genomic DNA
KY782246
EMBL· GenBank· DDBJ
ASC44329.1
EMBL· GenBank· DDBJ
Genomic DNA
KY797241
EMBL· GenBank· DDBJ
AUG83281.1
EMBL· GenBank· DDBJ
Genomic DNA
MK059514
EMBL· GenBank· DDBJ
QCB16902.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. Our staff consists of biologists and biochemists that are not trained to give medical advice.
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