A0A7U6KEU0 · A0A7U6KEU0_9FIRM
- ProteinDNA topoisomerase 3
- GenetopB
- StatusUniProtKB unreviewed (TrEMBL)
- Amino acids727 (go to sequence)
- Protein existenceInferred from homology
- Annotation score3/5
Function
function
Releases the supercoiling and torsional tension of DNA, which is introduced during the DNA replication and transcription, by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(5'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 3'-OH DNA strand. The free DNA strand then undergoes passage around the unbroken strand, thus removing DNA supercoils. Finally, in the religation step, the DNA 3'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone.
Catalytic activity
Cofactor
Features
Showing features for binding site, site, active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 10 | Mg2+ (UniProtKB | ChEBI); catalytic | ||||
Sequence: E | ||||||
Site | 62 | Interaction with DNA | ||||
Sequence: W | ||||||
Binding site | 106 | Mg2+ (UniProtKB | ChEBI); catalytic | ||||
Sequence: D | ||||||
Site | 169 | Interaction with DNA | ||||
Sequence: W | ||||||
Site | 177 | Interaction with DNA | ||||
Sequence: R | ||||||
Active site | 315 | O-(5'-phospho-DNA)-tyrosine intermediate | ||||
Sequence: Y | ||||||
Site | 317 | Interaction with DNA | ||||
Sequence: R |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | DNA binding | |
Molecular Function | DNA topoisomerase type I (single strand cut, ATP-independent) activity | |
Molecular Function | magnesium ion binding | |
Biological Process | DNA topological change |
Keywords
- Molecular function
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameDNA topoisomerase 3
- EC number
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageBacteria > Bacillota > Clostridia > Lachnospirales > Lachnospiraceae
Accessions
- Primary accessionA0A7U6KEU0
Proteomes
Structure
Family & Domains
Features
Showing features for domain, region.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 4-137 | Toprim | ||||
Sequence: KIVVLAEKPSVGRDIARVLNCKKKINGAIEGNEYIVTWGLGHLVTLCDPEKYEDRYKEWNLADLPMLPKHMKLEVMRQTGKQFSAVKAQLSRKDVKEVIIATDAGREGELVARWILEKAGCKLPMKRLWISSVT | ||||||
Region | 188-193 | Interaction with DNA | ||||
Sequence: SCGRVQ |
Sequence similarities
Belongs to the type IA topoisomerase family.
Family and domain databases
Sequence
- Sequence statusComplete
- Length727
- Mass (Da)82,315
- Last updated2021-06-02 v1
- Checksum57E4678EECBAD954
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AP018794 EMBL· GenBank· DDBJ | BBF42603.1 EMBL· GenBank· DDBJ | Genomic DNA |