A0A2H4PIM5 · A0A2H4PIM5_9CAUD
- ProteinFlap endonuclease
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids291 (go to sequence)
- Protein existenceInferred from homology
- Annotation score3/5
Function
function
Catalyzes both the 5'-exonucleolytic and structure-specific endonucleolytic hydrolysis of DNA branched nucleic acid molecules and probably plays a role in viral genome replication. Active on flap (branched duplex DNA containing a free single-stranded 5'-end), 5'overhangs and pseudo-Y structures. The substrates require a free, single-stranded 5' end, with endonucleolytic hydrolysis occurring at the junction of double- and single-stranded DNA. This function may be used for example to trim such branched molecules generated by Okazaki fragments synthesis during replication.
Catalytic activity
Cofactor
K+ (UniProtKB | Rhea| CHEBI:29103 )
Note: Binds divalent metal cations, probably Mg2+. In vitro low metal concentrations selectively stimulate the endonuclease reaction. Endonuclease activity is suggested to require only the first cation, whereas exonuclease activity is suggested to require binding of both. High pH favors the exonuclase activity whereas low pH favors the endonuclease activity. Metal ions enhance substrate binding. K+ is bound to the H3TH region.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 83 | DNA (UniProtKB | ChEBI) | ||||
Sequence: K | ||||||
Binding site | 130 | Mg2+ 2 (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Binding site | 130 | Mg2+ 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Binding site | 153 | Mg2+ 2 (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Binding site | 155 | Mg2+ 3 (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 155 | Mg2+ 2 (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Binding site | 201 | Mg2+ 3 (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 209 | K+ (UniProtKB | ChEBI) | ||||
Sequence: V | ||||||
Binding site | 212 | K+ (UniProtKB | ChEBI) | ||||
Sequence: I |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | 5'-flap endonuclease activity | |
Molecular Function | DNA binding | |
Molecular Function | double-stranded DNA 5'-3' DNA exonuclease activity | |
Molecular Function | metal ion binding | |
Biological Process | DNA replication, Okazaki fragment processing | |
Biological Process | viral DNA genome replication |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameFlap endonuclease
- EC number
- Short namesFEN
- Alternative names
Organism names
- Organism
- Taxonomic lineageViruses > Duplodnaviria > Heunggongvirae > Uroviricota > Caudoviricetes > Demerecviridae > Markadamsvirinae > Tequintavirus > Tequintavirus SP3
Accessions
- Primary accessionA0A2H4PIM5
Proteomes
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_5026409139 | 1-291 | Flap endonuclease | |||
Sequence: MSKSWGKFIEEEEAEMASRRNLMIVDGTNLGFRFKHNNSKKPFASSYVSTIQSLAKSYSARTTIVLGDKGKSAFRLEHLPEYKGNRDEKYSQRTEEEKALDEQFFEYLKDAFELCETTFPTFTIRGVEADDMAAYIVKLIGHLYDHVWLISTDGDWDTLLTDKVSRFSFTTRREYHLRDMYEHHNVDDVEQFISLKAIMGDLGDNIRGVEGIGAKRGYNIIREFGNVLDIIDQLPLPGKQKYIQNLNASEELLYRNLILVDLPTYCVDAIAAVGQDVLDKFTKDILEIAEQ |
Expression
Keywords
- Developmental stage
Structure
Family & Domains
Features
Showing features for domain, region.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 20-274 | 5'-3' exonuclease | ||||
Sequence: RNLMIVDGTNLGFRFKHNNSKKPFASSYVSTIQSLAKSYSARTTIVLGDKGKSAFRLEHLPEYKGNRDEKYSQRTEEEKALDEQFFEYLKDAFELCETTFPTFTIRGVEADDMAAYIVKLIGHLYDHVWLISTDGDWDTLLTDKVSRFSFTTRREYHLRDMYEHHNVDDVEQFISLKAIMGDLGDNIRGVEGIGAKRGYNIIREFGNVLDIIDQLPLPGKQKYIQNLNASEELLYRNLILVDLPTYCVDAIAAVG | ||||||
Region | 82-116 | Helical arch | ||||
Sequence: YKGNRDEKYSQRTEEEKALDEQFFEYLKDAFELCE | ||||||
Region | 188-224 | DNA-binding; H3TH | ||||
Sequence: DVEQFISLKAIMGDLGDNIRGVEGIGAKRGYNIIREF |
Domain
Three alpha-helices form a helical arch which forms a hole in the protein and through which the 5' flap of the scissile ssDNA is threaded.
Family and domain databases
Sequence
- Sequence statusComplete
- Length291
- Mass (Da)33,453
- Last updated2018-02-28 v1
- Checksum76BEFB66E7FDF7BA