› › Function and Biology

Chicken cytochrome BC1 complex with kresoxim-I-dimethyl bound

Source organism: Gallus gallus
Biochemical function: metal ion binding
Biological process: mitochondrial electron transport, ubiquinol to cytochrome c
Cellular component: mitochondrion

Quick links

EC 7.1.1.8: Quinol--cytochrome-c reductase

Reaction catalysed:
Quinol + 2 ferricytochrome c(Side 2) = quinone + 2 ferrocytochrome c(Side 2) + 2 H(+)(Side 2)
Systematic name:
Quinol:ferricytochrome-c oxidoreductase
Alternative Name(s):
  • CoQH(2)--cytochrome c oxidoreductase
  • Coenzyme Q--cytochrome c reductase
  • Coenzyme QH(2)--cytochrome c reductase
  • Complex III (mitochondrial electron transport)
  • Cytochrome bc1 complex
  • Dihydrocoenzyme Q--cytochrome c reductase
  • Mitochondrial electron transport complex III
  • QH(2):cytochrome c oxidoreductase
  • Reduced coenzyme Q-cytochrome c reductase
  • Reduced ubiquinone--cytochrome c oxidoreductase
  • Reduced ubiquinone--cytochrome c reductase, complex III (mitochondrial electron transport)
  • Ubihydroquinol:cytochrome c oxidoreductase
  • Ubiquinol--cytochrome c oxidoreductase
  • Ubiquinol--cytochrome c-2 oxidoreductase
  • Ubiquinol--cytochrome c1 oxidoreductase
  • Ubiquinol--cytochrome c2 reductase
  • Ubiquinol--cytochrome-c reductase
  • Ubiquinol:ferricytochrome-c oxidoreductase
  • Ubiquinone--cytochrome b-c(1) oxidoreductase
  • Ubiquinone--cytochrome c oxidoreductase
  • Ubiquinone--cytochrome-c oxidoreductase
  • Ubiquinone-cytochrome c reductase

GO terms

Biochemical function:
Biological process:
Cellular component:

Sequence families

Pfam Protein families (Pfam)
PF05193
Domain description: Peptidase M16 inactive domain
Occurring in:
  1. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i
  2. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF05193 (Peptidase M16 inactive domain) in Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i. Showing 1 copy in chain A.
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF05193 (Peptidase M16 inactive domain) in Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2. Showing 1 copy in chain L [auth O].

PF00675
Domain description: Insulinase (Peptidase family M16)
Occurring in:
  1. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i
  2. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF00675 (Insulinase (Peptidase family M16)) in Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i. Showing 1 copy in chain A.
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF00675 (Insulinase (Peptidase family M16)) in Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2. Showing 1 copy in chain L [auth O].

PF05365
Domain description: Ubiquinol-cytochrome C reductase, UQCRX/QCR9 like
Occurring in:
  1. Complex III subunit 9
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF05365 (Ubiquinol-cytochrome C reductase, UQCRX/QCR9 like) in Complex III subunit 9. Showing 1 copy in chain J.

PF09165
Domain description: Ubiquinol-cytochrome c reductase 8 kDa, N-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit 9

PF02320
Domain description: Ubiquinol-cytochrome C reductase hinge protein
Occurring in:
  1. Cytochrome b-c1 complex subunit 6
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF02320 (Ubiquinol-cytochrome C reductase hinge protein) in Cytochrome b-c1 complex subunit 6. Showing 1 copy in chain H.

PF02939
Domain description: UcrQ family
Occurring in:
  1. Cytochrome b-c1 complex subunit 8
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF02939 (UcrQ family) in Cytochrome b-c1 complex subunit 8. Showing 1 copy in chain G.

PF02271
Domain description: Ubiquinol-cytochrome C reductase complex 14kD subunit
Occurring in:
  1. Cytochrome b-c1 complex subunit 7
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF02271 (Ubiquinol-cytochrome C reductase complex 14kD subunit) in Cytochrome b-c1 complex subunit 7. Showing 1 copy in chain F.

PF00355
Domain description: Rieske [2Fe-2S] domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF00355 (Rieske [2Fe-2S] domain) in Cytochrome b-c1 complex subunit Rieske, mitochondrial. Showing 1 copy in chain E.

PF02921
Domain description: Ubiquinol cytochrome reductase transmembrane region
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF02921 (Ubiquinol cytochrome reductase transmembrane region) in Cytochrome b-c1 complex subunit Rieske, mitochondrial. Showing 1 copy in chain E.

PF02167
Domain description: Cytochrome C1 family
Occurring in:
  1. Cytochrome c domain-containing protein
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF02167 (Cytochrome C1 family) in Cytochrome c. Showing 1 copy in chain D.

PF00032
Domain description: Cytochrome b(C-terminal)/b6/petD
Occurring in:
  1. Cytochrome b
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF00032 (Cytochrome b(C-terminal)/b6/petD) in Cytochrome b. Showing 1 copy in chain C.

PF00033
Domain description: Cytochrome b/b6/petB
Occurring in:
  1. Cytochrome b
The deposited structure of PDB entry 3l72 contains 2 copies of Pfam domain PF00033 (Cytochrome b/b6/petB) in Cytochrome b. Showing 1 copy in chain C.

InterPro InterPro annotations
IPR002326
Domain description: Cytochrome c1
Occurring in:
  1. Cytochrome c domain-containing protein
IPR011249
Domain description: Metalloenzyme, LuxS/M16 peptidase-like
Occurring in:
  1. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i
  2. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2
IPR003197
Domain description: Cytochrome b-c1 complex subunit 7
Occurring in:
  1. Cytochrome b-c1 complex subunit 7
IPR005805
Domain description: Rieske iron-sulphur protein, C-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR005798
Domain description: Cytochrome b/b6, C-terminal
Occurring in:
  1. Cytochrome b
IPR005797
Domain description: Cytochrome b/b6, N-terminal domain
Occurring in:
  1. Cytochrome b
IPR008027
Domain description: Cytochrome b-c1 complex subunit 9
Occurring in:
  1. Complex III subunit 9
IPR036656
Domain description: Cytochrome b-c1 complex subunit 9 superfamily
Occurring in:
  1. Complex III subunit 9
IPR003422
Domain description: Cytochrome b-c1 complex, subunit 6
Occurring in:
  1. Cytochrome b-c1 complex subunit 6
IPR036811
Domain description: Ubiquinol-cytochrome C reductase hinge domain superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit 6
IPR036642
Domain description: Cytochrome b-c1 complex subunit 8 superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit 8
IPR004205
Domain description: Cytochrome b-c1 complex subunit 8
Occurring in:
  1. Cytochrome b-c1 complex subunit 8
IPR036544
Domain description: Cytochrome b-c1 complex subunit 7 superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit 7
IPR017941
Domain description: Rieske [2Fe-2S] iron-sulphur domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR036922
Domain description: Rieske [2Fe-2S] iron-sulphur domain superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR036909
Domain description: Cytochrome c-like domain superfamily
Occurring in:
  1. Cytochrome c domain-containing protein
IPR007863
Domain description: Peptidase M16, C-terminal
Occurring in:
  1. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i
  2. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2
IPR011765
Domain description: Peptidase M16, N-terminal
Occurring in:
  1. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i
  2. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2
IPR015248
Domain description: Ubiquinol-cytochrome c reductase iron-sulphur subunit, N-terminal
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
IPR011070
Domain description: Globular protein, non-globular alpha/beta subunit
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
IPR023184
Domain description: Ubiquinol-cytochrome C reductase hinge domain
Occurring in:
  1. Cytochrome b-c1 complex subunit 6
IPR006317
Domain description: Ubiquinol-cytochrome c reductase, iron-sulphur subunit
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR014349
Domain description: Rieske iron-sulphur protein
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR004192
Domain description: Cytochrome b-c1 complex subunit Rieske, transmembrane domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR037008
Domain description: Cytochrome bc1 complex subunit Rieske, transmembrane domain superfamily
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
IPR021157
Domain description: Cytochrome c1, transmembrane anchor, C-terminal
Occurring in:
  1. Cytochrome c domain-containing protein
IPR009056
Domain description: Cytochrome c-like domain
Occurring in:
  1. Cytochrome c domain-containing protein
IPR036150
Domain description: Cytochrome b/b6, C-terminal domain superfamily
Occurring in:
  1. Cytochrome b
IPR016174
Domain description: Di-haem cytochrome, transmembrane
Occurring in:
  1. Cytochrome b
IPR030689
Domain description: Cytochrome b
Occurring in:
  1. Cytochrome b
IPR027387
Domain description: Cytochrome b/b6-like domain superfamily
Occurring in:
  1. Cytochrome b

Structure domains

CATH CATH domains
3.30.830.10
Class: Alpha Beta
Architecture: 2-Layer Sandwich
Topology: Cytochrome Bc1 Complex; Chain A, domain 1
Homology: Metalloenzyme, LuxS/M16 peptidase-like
Occurring in:
  1. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i
  2. Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2
The deposited structure of PDB entry 3l72 contains 4 copies of CATH domain 3.30.830.10 (Cytochrome Bc1 Complex; Chain A, domain 1) in Mitochondrial ubiquinol-cytochrome-c reductase complex core protein i. Showing 2 copies in chain A.
The deposited structure of PDB entry 3l72 contains 4 copies of CATH domain 3.30.830.10 (Cytochrome Bc1 Complex; Chain A, domain 1) in Mitochondrial ubiquinol-cytochrome-c reductase complex core protein 2. Showing 2 copies in chain L [auth O].
1.20.5.260
Class: Mainly Alpha
Architecture: Up-down Bundle
Topology: Single alpha-helices involved in coiled-coils or other helix-helix interfaces
Homology: Cytochrome b-c1 complex subunit 9
Occurring in:
  1. Complex III subunit 9
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.20.5.260 (Single alpha-helices involved in coiled-coils or other helix-helix interfaces) in Complex III subunit 9. Showing 1 copy in chain J.
2.10.210.10
Class: Mainly Beta
Architecture: Ribbon
Topology: Cytochrome Bc1 Complex; Chain I
Homology: Cytochrome Bc1 Complex; Chain I
Occurring in:
  1. Cytochrome b-c1 complex subunit 9
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 2.10.210.10 (Cytochrome Bc1 Complex; Chain I) in Cytochrome b-c1 complex subunit 9. Showing 1 copy in chain I.
1.10.287.20
Class: Mainly Alpha
Architecture: Orthogonal Bundle
Topology: Helix Hairpins
Homology: Ubiquinol-cytochrome C reductase hinge domain
Occurring in:
  1. Cytochrome b-c1 complex subunit 6
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.10.287.20 (Helix Hairpins) in Cytochrome b-c1 complex subunit 6. Showing 1 copy in chain H.
1.20.5.210
Class: Mainly Alpha
Architecture: Up-down Bundle
Topology: Single alpha-helices involved in coiled-coils or other helix-helix interfaces
Homology: Cytochrome b-c1 complex subunit 8
Occurring in:
  1. Cytochrome b-c1 complex subunit 8
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.20.5.210 (Single alpha-helices involved in coiled-coils or other helix-helix interfaces) in Cytochrome b-c1 complex subunit 8. Showing 1 copy in chain G.
1.10.1090.10
Class: Mainly Alpha
Architecture: Orthogonal Bundle
Topology: Cytochrome Bc1 Complex; Chain F
Homology: Cytochrome b-c1 complex subunit 7
Occurring in:
  1. Cytochrome b-c1 complex subunit 7
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.10.1090.10 (Cytochrome Bc1 Complex; Chain F) in Cytochrome b-c1 complex subunit 7. Showing 1 copy in chain F.
2.102.10.10
Class: Mainly Beta
Architecture: 3-layer Sandwich
Topology: Rieske Iron-sulfur Protein
Homology: Rieske [2Fe-2S] iron-sulphur domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 2.102.10.10 (Rieske Iron-sulfur Protein) in Cytochrome b-c1 complex subunit Rieske, mitochondrial. Showing 1 copy in chain E.
1.20.5.270
Class: Mainly Alpha
Architecture: Up-down Bundle
Topology: Single alpha-helices involved in coiled-coils or other helix-helix interfaces
Homology: Ubiquinol cytochrome reductase, transmembrane domain
Occurring in:
  1. Cytochrome b-c1 complex subunit Rieske, mitochondrial
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.20.5.270 (Single alpha-helices involved in coiled-coils or other helix-helix interfaces) in Cytochrome b-c1 complex subunit Rieske, mitochondrial. Showing 1 copy in chain E.
1.20.5.100
Class: Mainly Alpha
Architecture: Up-down Bundle
Topology: Single alpha-helices involved in coiled-coils or other helix-helix interfaces
Homology: Cytochrome c1, transmembrane anchor, C-terminal
Occurring in:
  1. Cytochrome c domain-containing protein
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.20.5.100 (Single alpha-helices involved in coiled-coils or other helix-helix interfaces) in Cytochrome c. Showing 1 copy in chain D.
1.10.760.10
Class: Mainly Alpha
Architecture: Orthogonal Bundle
Topology: Cytochrome Bc1 Complex; Chain D, domain 2
Homology: Cytochrome c-like domain
Occurring in:
  1. Cytochrome c domain-containing protein
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.10.760.10 (Cytochrome Bc1 Complex; Chain D, domain 2) in Cytochrome c. Showing 1 copy in chain D.
1.20.810.10
Class: Mainly Alpha
Architecture: Up-down Bundle
Topology: Cytochrome Bc1 Complex; Chain C
Homology: Cytochrome Bc1 Complex; Chain C
Occurring in:
  1. Cytochrome b
The deposited structure of PDB entry 3l72 contains 2 copies of CATH domain 1.20.810.10 (Cytochrome Bc1 Complex; Chain C) in Cytochrome b. Showing 1 copy in chain C.

Quick links