A0A1R7Q9V1 · A0A1R7Q9V1_ACIJO
- ProteinRecBCD enzyme subunit RecB
- GenerecB
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids1250 (go to sequence)
- Protein existenceInferred from homology
- Annotation score4/5
Function
function
A helicase/nuclease that prepares dsDNA breaks (DSB) for recombinational DNA repair. Binds to DSBs and unwinds DNA via a highly rapid and processive ATP-dependent bidirectional helicase activity. Unwinds dsDNA until it encounters a Chi (crossover hotspot instigator) sequence from the 3' direction. Cuts ssDNA a few nucleotides 3' to the Chi site. The properties and activities of the enzyme are changed at Chi. The Chi-altered holoenzyme produces a long 3'-ssDNA overhang and facilitates RecA-binding to the ssDNA for homologous DNA recombination and repair. Holoenzyme degrades any linearized DNA that is unable to undergo homologous recombination. In the holoenzyme this subunit contributes ATPase, 3'-5' helicase, exonuclease activity and loads RecA onto ssDNA.
Miscellaneous
In the RecBCD complex, RecB has a slow 3'-5' helicase, an exonuclease activity and loads RecA onto ssDNA, RecD has a fast 5'-3' helicase activity, while RecC stimulates the ATPase and processivity of the RecB helicase and contributes to recognition of the Chi site.
Catalytic activity
- ATP + H2O = ADP + phosphate + H+
Cofactor
Note: Binds 1 Mg2+ ion per subunit.
Features
Showing features for binding site, active site.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Binding site | 30-37 | ATP (UniProtKB | ChEBI) | |||
Binding site | 994 | Mg2+ (UniProtKB | ChEBI) | |||
Binding site | 1121 | Mg2+ (UniProtKB | ChEBI) | |||
Active site | 1134 | For nuclease activity | |||
Binding site | 1134 | Mg2+ (UniProtKB | ChEBI) | |||
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytosol | |
Cellular Component | exodeoxyribonuclease V complex | |
Molecular Function | 3'-5' DNA helicase activity | |
Molecular Function | ATP binding | |
Molecular Function | ATP hydrolysis activity | |
Molecular Function | DNA binding | |
Molecular Function | exodeoxyribonuclease V activity | |
Molecular Function | isomerase activity | |
Molecular Function | magnesium ion binding | |
Biological Process | double-strand break repair via homologous recombination |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameRecBCD enzyme subunit RecB
- EC number
- Alternative names
Gene names
Organism names
- Organism
- Strain
- Taxonomic lineageBacteria > Pseudomonadota > Gammaproteobacteria > Moraxellales > Moraxellaceae > Acinetobacter
Accessions
- Primary accessionA0A1R7Q9V1
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Interaction
Subunit
Heterotrimer of RecB, RecC and RecD. All subunits contribute to DNA-binding. Interacts with RecA.
Structure
Family & Domains
Features
Showing features for region, domain.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Region | 1-905 | DNA-binding and helicase activity, interacts with RecC | |||
Domain | 9-492 | UvrD-like helicase ATP-binding | |||
Domain | 493-777 | UvrD-like helicase C-terminal | |||
Region | 926-1250 | Nuclease activity, interacts with RecD and RecA | |||
Domain
The C-terminal domain has nuclease activity and interacts with RecD. It interacts with RecA, facilitating its loading onto ssDNA.
The N-terminal DNA-binding domain is a ssDNA-dependent ATPase and has ATP-dependent 3'-5' helicase function. This domain interacts with RecC.
Sequence similarities
Belongs to the helicase family. UvrD subfamily.
Family and domain databases
Sequence
- Sequence statusComplete
- Length1,250
- Mass (Da)143,887
- Last updated2017-04-12 v1
- Checksum427DE586E9E67ED5
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
FUUY01000002 EMBL· GenBank· DDBJ | SJX21041.1 EMBL· GenBank· DDBJ | Genomic DNA |