Recombinant human Topoisomerase I protein (ab3808)



  • NatureRecombinant
  • SourceBaculovirus
  • Amino Acid Sequence
    • SpeciesHuman
    • Molecular weight91 kDa


Our Abpromise guarantee covers the use of ab3808 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

  • Biological activity

    A unit of topo I can relax 0.2 ug pGEM 5Z DNA in 30 min at 37oC. The enzyme is supplied at a nominal concentration of approximately 2 units/ul.

  • Applications

    Functional Studies

    Western blot

  • FormLiquid
  • Additional notes

    Quality Control Tests: 1. A test for nuclease contamination is carried out by assaying for the formation of linear KDNA and linear plasmid DNA. Incubation with KDNA or supercoiled pGEM 5Z DNA (4 hrs. at 37ºC in the presence of 10 mM MgCl2) is performed. Linear DNA or breakdown products are not generated under these conditions. 2. A check for cross contamination with Topo II is negative. There must be no decatenation of KDNA in topo II reaction conditions. 3. Performance in converting super-coiled DNA to relaxed DNA.

  • Concentration information loading...

Preparation and Storage

  • Stability and Storage

    Shipped at 4°C. Upon delivery aliquot and store at -20°C or -80°C. Avoid repeated freeze / thaw cycles.

    10 mM Tris-Cl, pH 7.5, 100 mM NaCl, 100 mM imidazole, 0.5 mM PMSF, 1 mM DTT, and 10 % glycerol

    This product is an active protein and may elicit a biological response in vivo, handle with caution.

General Info

  • Alternative names
    • DNA topoisomerase 1
    • DNA topoisomerase I
    • NUP98 fusion gene
    • TOP 1
    • TOP I
    • TOP1
    • TOP1_HUMAN
    • TOPI
    • Topoisomerase (DNA) I
    • Topoisomerase 1
    • Topoisomerase1
    • TopoisomeraseI
    • Type I DNA topoisomerase
    see all
  • FunctionThe reaction catalyzed by topoisomerases leads to the conversion of one topological isomer of DNA to another.
  • Involvement in diseaseNote=A chromosomal aberration involving TOP1 is found in a form of therapy-related myelodysplastic syndrome. Translocation t(11;20)(p15;q11) with NUP98.
  • Sequence similaritiesBelongs to the eukaryotic type I topoisomerase family.
  • Post-translational
    Sumoylated. Lys-117 is the main site of sumoylation. Sumoylation plays a role in partitioning TOP1 between nucleoli and nucleoplasm. Levels are dramatically increased on camptothecin (CPT) treatment.
  • Cellular localizationNucleus > nucleolus. Nucleus > nucleoplasm. Diffuse nuclear localization with some enrichment in nucleoli. On CPT treatment, cleared from nucleoli into nucleoplasm. Sumolyated forms found in both nucleoplasm and nucleoli.
  • Information by UniProt

Recombinant human Topoisomerase I protein images

  • Coomassie Blue staining of purified human DNA topoisomerase protein.
  • A unit of topo I incubated with 0.2 µg pGEM 5Z DNA in 30 min at 37ºC.

References for Recombinant human Topoisomerase I protein (ab3808)

ab3808 has not yet been referenced specifically in any publications.

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