A0A3Q8QR27 · A0A3Q8QR27_HUMAN
- ProteinCytochrome b
- GeneCYTB
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids380 (go to sequence)
- Protein existenceInferred from homology
- Annotation score2/5
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:
Note: Binds 2 heme groups non-covalently.
Note: Binds 2 heme groups non-covalently.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 83 | Fe (UniProtKB | ChEBI) of heme b b562 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 97 | Fe (UniProtKB | ChEBI) of heme b b566 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 182 | Fe (UniProtKB | ChEBI) of heme b b562 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 196 | Fe (UniProtKB | ChEBI) of heme b b566 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 201 | a ubiquinone (UniProtKB | ChEBI) | ||||
Sequence: H |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | mitochondrial inner membrane | |
Cellular Component | respiratory chain complex III | |
Molecular Function | metal ion binding | |
Molecular Function | ubiquinol-cytochrome-c reductase activity | |
Biological Process | respiratory electron transport chain |
Keywords
- Biological process
- Ligand
Names & Taxonomy
Protein names
- Recommended nameCytochrome b
Gene names
Encoded on
- Mitochondrion
Organism names
- Organism
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo
Accessions
- Primary accessionA0A3Q8QR27
Subcellular Location
UniProt Annotation
GO Annotation
Membrane ; Multi-pass membrane protein
Mitochondrion inner membrane ; Multi-pass membrane protein
Features
Showing features for transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Transmembrane | 30-56 | Helical | ||||
Sequence: WWNFGSLLGACLILQITTGLFLAMHYS | ||||||
Transmembrane | 77-98 | Helical | ||||
Sequence: WIIRYLHANGASMFFICLFLHI | ||||||
Transmembrane | 113-133 | Helical | ||||
Sequence: WNIGIILLLATMATAFMGYVL | ||||||
Transmembrane | 140-158 | Helical | ||||
Sequence: FWGATVITNLLSAIPYIGT | ||||||
Transmembrane | 178-200 | Helical | ||||
Sequence: FFTFHFILPFIIAALAALHLLFL | ||||||
Transmembrane | 229-246 | Helical | ||||
Sequence: ALGLLLFILSLMTLTLFS | ||||||
Transmembrane | 288-308 | Helical | ||||
Sequence: LGGVLALLLSILILAMIPILH | ||||||
Transmembrane | 320-339 | Helical | ||||
Sequence: LSQSLYWLLAADLLILTWIG | ||||||
Transmembrane | 345-372 | Helical | ||||
Sequence: YPFTIIGQVASVLYFTTILILMPTISLI |
Keywords
- Cellular component
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.
Structure
Family & Domains
Features
Showing features for domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 1-209 | Cytochrome b/b6 N-terminal region profile | ||||
Sequence: MTPMRKINPLMKLINHSLIDLPTPSNISAWWNFGSLLGACLILQITTGLFLAMHYSPDASTAFSSIAHITRNVNYGWIIRYLHANGASMFFICLFLHIGRGLYYGSFLYSETWNIGIILLLATMATAFMGYVLPWGQMSFWGATVITNLLSAIPYIGTDLVQWIWGGYSVDSPTLTRFFTFHFILPFIIAALAALHLLFLHETGSNNPL | ||||||
Domain | 210-380 | Cytochrome b/b6 C-terminal region profile | ||||
Sequence: GITSHSDKITFHPYYTIKDALGLLLFILSLMTLTLFSPDLLGDPDNYTLANPLNTPPHIKPEWYFLFAYTILRSVPNKLGGVLALLLSILILAMIPILHMSKQQSMMFRPLSQSLYWLLAADLLILTWIGGQPVSYPFTIIGQVASVLYFTTILILMPTISLIENKMLKWA |
Sequence similarities
Belongs to the cytochrome b family.
Keywords
- Domain
Family and domain databases
Sequence
- Sequence statusComplete
- Length380
- Mass (Da)42,665
- Last updated2019-04-10 v1
- ChecksumF65500A6FD0620A2