P0ABJ9 · CYDA_ECOLI
- ProteinCytochrome bd-I ubiquinol oxidase subunit 1
- GenecydA
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids522 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
A terminal oxidase that produces a proton motive force by the vectorial transfer of protons across the inner membrane. It is the component of the aerobic respiratory chain of E.coli that predominates when cells are grown at low aeration. Generates a proton motive force using protons and electrons from opposite sides of the membrane to generate H2O, transferring 1 proton/electron.
Catalytic activity
- 2 a ubiquinol + O2(in) + 4 H+(in) = 2 a ubiquinone + 2 H2O(in) + 4 H+(out)
2 a ubiquinol RHEA-COMP:9566 + O2 (in)CHEBI:15379+ 4 H+ (in)CHEBI:15378= 2 a ubiquinone RHEA-COMP:9565 + 2 H2O (in)CHEBI:15377+ 4 H+ (out)CHEBI:15378
Cofactor
Protein has several cofactor binding sites:
Note: Binds 1 protoheme IX center (heme b558) per subunit.
Note: Binds 1 protoheme IX center (heme b595, originally called cytochrome a1) per heterodimer, in conjunction with CydB.
Note: Binds 1 iron-chlorin (heme d or cytochrome d) per heterodimer, in conjunction with CydB.
Activity regulation
90% inhibited by cyanide and 2-heptyl-4-hydroxyquinoline N-oxide, at 1 mM and 40 uM respectively.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
0.1 mM | ubiquinol-1 | |||||
0.28 mM | 2,3,5,6-tetramethyl-p-phenylenediamine | |||||
0.68 mM | N,N,N',N'-tetramethyl-p-phenylenediamine |
Vmax | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|
383 μmol/min/mg | for ubiquinol-1 | ||||
270 μmol/min/mg | for 2,3,5,6-tetramethyl-p-phenylenediamine | ||||
126 μmol/min/mg | for N,N,N',N'-tetramethyl-p-phenylenediamine |
pH 7.0, 37 degrees Celsius.
Pathway
Energy metabolism; oxidative phosphorylation.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Binding site | 19 | Fe (UniProtKB | ChEBI) of heme b b595 (UniProtKB | ChEBI); axial binding residue | |||
Binding site | 186 | Fe (UniProtKB | ChEBI) of heme b b558 (UniProtKB | ChEBI); axial binding residue | |||
Binding site | 393 | Fe (UniProtKB | ChEBI) of heme b b558 (UniProtKB | ChEBI); axial binding residue | |||
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytochrome complex | |
Cellular Component | membrane | |
Cellular Component | plasma membrane | |
Molecular Function | electron transfer activity | |
Molecular Function | heme binding | |
Molecular Function | metal ion binding | |
Molecular Function | oxidoreductase activity, acting on diphenols and related substances as donors | |
Molecular Function | oxidoreductase activity, acting on diphenols and related substances as donors, oxygen as acceptor | |
Biological Process | aerobic electron transport chain | |
Biological Process | oxidative phosphorylation |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Protein family/group databases
Names & Taxonomy
Protein names
- Recommended nameCytochrome bd-I ubiquinol oxidase subunit 1
- EC number
- Alternative names
Gene names
Organism names
- Organism
- Strains
- Taxonomic lineageBacteria > Pseudomonadota > Gammaproteobacteria > Enterobacterales > Enterobacteriaceae > Escherichia
Accessions
- Primary accessionP0ABJ9
- Secondary accessions
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Cell inner membrane ; Multi-pass membrane protein
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Topological domain | 1-15 | Periplasmic | |||
Transmembrane | 16-35 | Helical | |||
Topological domain | 36-54 | Cytoplasmic | |||
Transmembrane | 55-69 | Helical | |||
Topological domain | 70-96 | Periplasmic | |||
Transmembrane | 97-114 | Helical | |||
Topological domain | 115-128 | Cytoplasmic | |||
Transmembrane | 129-146 | Helical | |||
Topological domain | 147-186 | Periplasmic | |||
Transmembrane | 187-203 | Helical | |||
Topological domain | 204-219 | Cytoplasmic | |||
Transmembrane | 220-235 | Helical | |||
Topological domain | 236-390 | Periplasmic | |||
Transmembrane | 391-407 | Helical | |||
Topological domain | 408-423 | Cytoplasmic | |||
Transmembrane | 424-441 | Helical | |||
Topological domain | 442-472 | Periplasmic | |||
Transmembrane | 473-487 | Helical | |||
Topological domain | 488-522 | Cytoplasmic | |||
Keywords
- Cellular component
Phenotypes & Variants
Disruption phenotype
A double cydA/cydB deletion shows increased sensitivity to reductant (beta-mercapoethanol).
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Mutagenesis | 19 | Loss of cytochrome b595 and heme d, no aerobic growth, complex assembles. | |||
Mutagenesis | 86 | No effect. | |||
Mutagenesis | 126 | Loss of all cofactors, no aerobic growth, complex assembles. | |||
Mutagenesis | 126 | No effect. | |||
Mutagenesis | 186 | Loss of cytochrome b558, no aerobic growth, complex assembles, this subunit is more susceptible to proteolysis. | |||
Mutagenesis | 314 | Grows aerobically, has altered cytochrome b/d ratio, complex assembles. | |||
Mutagenesis | 314 | Loss of cytochrome b595 and heme d, no aerobic growth, loss of complex. | |||
Mutagenesis | 393 | Cytochrome b558 shifts to a high spin configuration, complex assembles. Retains about 1% quinol oxidoreductase activity after purification. | |||
Mutagenesis | 510 | No effect. | |||
Expression
Induction
Under conditions of low aeration, in stationary phase (at protein level).
Interaction
Subunit
Heterodimer of subunits I and II. Probably interacts with CydX, and overexpressed AppX.
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | IntAct | |
---|---|---|---|---|---|
BINARY | P0ABJ9 | cydB P0ABK2 | 5 | EBI-906928, EBI-1213195 |
Complex viewer
Protein-protein interaction databases
Structure
Sequence
- Sequence statusComplete
- Length522
- Mass (Da)58,205
- Last updated2005-10-25 v1
- MD5 Checksum24E689B003B14408A49A151692CF629C
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Sequence conflict | 213 | in Ref. 1; AAA18804 | |||
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
J03939 EMBL· GenBank· DDBJ | AAA18804.1 EMBL· GenBank· DDBJ | Unassigned DNA | ||
U00096 EMBL· GenBank· DDBJ | AAC73827.2 EMBL· GenBank· DDBJ | Genomic DNA | ||
AP009048 EMBL· GenBank· DDBJ | BAA35399.1 EMBL· GenBank· DDBJ | Genomic DNA |