FB2026_03 , released September 17, 2026
FB2026_03 , released September 17, 2026
CV Term Report
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General Information
Term DNA topoisomerase type I (single strand cut, ATP-independent) activity ID (Ontology) GO:0003917 (Gene Ontology)
Definition Catalysis of a DNA topological transformation by transiently cleaving one DNA strand at a time to allow passage of another strand; changes the linking number by +1 per catalytic cycle.[ PubMed:8811192 ]
Also Known As "type I DNA topoisomerase activity" ; "type I topoisomerase activity"
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Data ClassFieldDirect annotations
Genes (FBgn)GO_MOLECULAR_FUNCTION
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 DNA topoisomerase type I (single strand cut, ATP-independent) activity (all annotations which use CV term, excluding "NOT" statements)
     enables | DNA topoisomerase type I (single strand cut, ATP-independent) activity       --
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nucleic acid conformation isomerase activity__
catalytic activity, acting on DNA_____________|
                                              DNA topoisomerase activity
                                               |__DNA topoisomerase type I (single strand cut, ATP-independent) activity  5 rec.
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Is a DNA topoisomerase activity
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Synonyms
  • "deoxyribonucleate topoisomerase" BROAD
    "DNA topoisomerase I activity" NARROW
    "nicking-closing enzyme activity" RELATED[ EC:5 ]
    "omega-protein activity" RELATED[ EC:5 ]
    "relaxing enzyme activity" RELATED[ EC:5 ]
    "swivelase activity" RELATED[ EC:5 ]
    "topoisomerase" BROAD[ EC:5 ]
    "type I DNA topoisomerase activity" EXACT
    "type I topoisomerase activity" EXACT
    "untwisting enzyme activity" RELATED[ EC:5 ]
Secondary IDs
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EC:5.6.2.1
MetaCyc:5.99.1.2-RXN
Reactome:R-HSA-9914922 "TOP3A (Topoisomerase 3a) decatenates mitochondrial DNA"