A0A8I0MK77 · A0A8I0MK77_CITAM

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.

Caution

The sequence shown here is derived from an EMBL/GenBank/DDBJ whole genome shotgun (WGS) entry which is preliminary data.

Catalytic activity

Cofactor

Mg2+ (UniProtKB | Rhea| CHEBI:18420 )

Note: Binds 1 Mg2+ ion per subunit.

Features

Showing features for binding site, active site.

TypeIDPosition(s)Description
Binding site23-30ATP (UniProtKB | ChEBI)
Binding site956Mg2+ (UniProtKB | ChEBI)
Binding site1067Mg2+ (UniProtKB | ChEBI)
Active site1080For nuclease activity
Binding site1080Mg2+ (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentcytosol
Cellular Componentexodeoxyribonuclease V complex
Molecular Function3'-5' DNA helicase activity
Molecular FunctionATP binding
Molecular FunctionDNA binding
Molecular Functionexodeoxyribonuclease V activity
Molecular Functionisomerase activity
Molecular Functionmagnesium ion binding
Biological Processdouble-strand break repair via homologous recombination

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    RecBCD enzyme subunit RecB
  • EC number
  • Alternative names
    • DNA 3'-5' helicase subunit RecB
    • Exonuclease V subunit RecB
      (ExoV subunit RecB
      )
    • Helicase/nuclease RecBCD subunit RecB

Gene names

    • Name
      recB
    • ORF names
      FOT72_10995

Organism names

  • Taxonomic identifier
  • Organism
  • Strain
    • CA13304
  • Taxonomic lineage
    Bacteria > Pseudomonadota > Gammaproteobacteria > Enterobacterales > Enterobacteriaceae > Citrobacter

Accessions

  • Primary accession
    A0A8I0MK77

Proteomes

Subcellular Location

Interaction

Subunit

Heterotrimer of RecB, RecC and RecD. All subunits contribute to DNA-binding. Interacts with RecA.

Family & Domains

Features

Showing features for region, domain.

TypeIDPosition(s)Description
Region1-883DNA-binding and helicase activity, interacts with RecC
Domain2-450UvrD-like helicase ATP-binding
Domain480-746UvrD-like helicase C-terminal
Region900-1181Nuclease 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 status
    Complete
  • Length
    1,181
  • Mass (Da)
    133,264
  • Last updated
    2022-01-19 v1
  • Checksum
    AFD7231CF87A64D6
MNDVAESLDPLRLPLTGERLIEASAGTGKTFTIAALYLRLLLGLGGSSAFPRPLTVEELLVVTFTEAATEELRGRIRSNIHELRIACLRESTDNPLYARLLDEIDDKKQAAQWLLLAERQMDEAAVFTIHGFCQRMLSLNAFESGMLFEQQLIEDESLLRYQACADFWRRHCYPLPREIAQVVFETWKGPQALLADINRYLQGEAPVIKAPPPDDETLASRHQQIVQRINALKQQWCDAVGELEAVMEASGIDRRKFNRGNQGKWIEKISAWAQSGTQSYQLPEALEKFSQRFLEDRTKEGGVVPQHPLFVAIDELLAEPLTLRDLVITRALAEIRETVAKEKRRRGELGFDDMLSRLDSALRSESGDALSAAIRTRFPVAMIDEFQDTDPQQYRIFRRIWQHQPDTALLLIGDPKQAIYAFRGADIFTYMKARSEVSAHYTLDTNWRSAPGMVNSVNRLFSQMDDAFMFREIPFQPVKYAEKNQSLRFEFHGETQPAMTMWLMEGESCGIGDYQSHMAQVCAAQIRDWLKAGLCGEAMLISGRDVRPVSAADISVLVRSRQEAALVRDALTQLAIPSVYLSNRDSVFETLEAQEMLWVLQAVMAPEKENTLRSALATSMMGLNARDIDMLNGNENAWDQVVDEFVGYRQIWQKRGVMPMLRALMSARQIAENLLATAGGERRLTDILHISELLQEAASQLESEHALVRWLSQHILEPDSNASSQQMRLESDSHLVQIVTIHKSKGLEYPLVWLPFITHFRVQDQAFYHDRNSFEAVLDLSEADESVALAEAERLAEDLRLLYVALTRSVWHCSLGVAPLVRRRGDKKGDTDVHQSALGRLLQKGEPMDAPGLRAAIDAVCDENIVCRIPEAVSMEPLPGAVASEASLNARRVQRTPGDNWRVTSYSGLQQRGHGIAQDLMPRLDIDAAGVGEVVEEPELTPHQFPRGASPGTFLHSLFEDLDFTQPVEAVWVQEKLELGGYDANWEPIITAWVTAILHAPLNESGVSLSQLSAREKQVEMEFYLPISQPLIAENLDALIRQFDPLSAGCPPLEFAQVRGMLKGFIDLVFRHNGRYYLLDYKSNWLGENSAAYTPEAMAAAMQAHRYDLQYQLYTLALHRYLRHRIADYDYERHFGGVIYLFLRGVDSTQPQQGIYTTRPAGELIARMDEMFAGMALEEAS

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
VKME01000008
EMBL· GenBank· DDBJ
MBE0128522.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

Disclaimer

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