Brand:  VPCIR Enzymes

SKU: N/A Category: Tags: , GTIN: 5744002620006

Human TOP1 Enzyme

350.00 + excl. VAT

High purity, catalytically active hTOP1 Enzyme overexpressed in yeast and purified to single band homogeneity.


Research in Cancer, Research in Chronic diseases, Research in Infectious diseases




1.5 µg ≥ 1,500 units, 3.5 µg ≥ 3,500 units, 10 µg ≥ 10,000 units


Single-pack, 2-pack, 3-pack


Not IATA restricted


Must be stored at -18°C to -20°C upon arrival


Human topoisomerase 1 (hTOP1) is supplied in Dilution Buffer at a minimum concentration of 30ng/µl, corresponding to at least 30 U/µl. 1 U of hTOP1 relaxes 0.5 µg of supercoiled pUC19 when incubated in Reaction Buffer and 150 mM NaCl in a total reaction volume of 20 µl at 37 °C for 30 minutes. The purity and the concentration of the enzyme has been determined by SDS-PAGE followed by Coomassie brilliant-blue staining. The intensity of the hTOP1 band has been estimated by densitometry and quantified by using ImageJ software comparing with a protein standard of known concentration. The hTOP1 enzyme is free from nucleases contaminations and 80% pure as determined by SDS-PAGE analysis. The enzyme preparation is highly stable and recommended for activity assays, including cleavage-ligation experiments, equilibrium, nicking and relaxation assays. The hTOP1 enzyme is supplied together with: • Dilution Buffer: 5 mM Tris-HCl pH 7.5, 400 mM NaCl, 1mM DTT, 50% glycerol. • Reaction Buffer 10x: 100 mM Tris-HCl pH 7.5; 50 mM MgCl2, 50 mM CaCl2; 50 µg/ml BSA. • Nucleases-free water. • 1M NaCl.


Recombinant non-tagged hTOP1 is prepared by overexpressing the enzyme in Saccharomyces cerevisiae followed by purification by affinity chromatography adapted from Knudsen et al, J. Chrom. 1996, DOI: 10.1016/0378-4347(96)00152-1

The enzyme is shipped cooled by gel packs and must be stored at -18°C to -20°C upon arrival. The temperature must be controlled to avoid that the enzyme preparation solidifies. This would destroy the enzyme integrity and cause a drop of the hTOP1 activity. The enzyme has a lifetime of 12 months when stored under optimal conditions.

Certificate of Analysis for Human topoisomerase 1 (hTOP1).


Download PDF

Safety Data Sheet for Human TOP1 Enzyme products.

QR-code for Human TOP1 Enzyme SDS


  1. Leppard, J.B.; Champoux, J.J. Human DNA topoisomerase I: relaxation, roles, and damage control. Chromosoma 2005, 114, 75–85, doi:10.1007/s00412-005-0345-5.
  2. Nitiss, J.L.; Soans, E.; Rogojina, A.; Seth, A.; Mishina, M. Topoisomerase assays. Curr. Protoc. Pharmacol. 2012, Chapter 3, Unit 3.3., doi:10.1002/0471141755.ph0303s57.
  3. Andersen, M.B.; Tesauro, C.; Gonzalez, M.; Kristoffersen, E.L.; Alonso, C.; Rubiales, G.; Coletta, A.; Frøhlich, R.; Stougaard, M.; Ho, Y.-P.; et al. Advantages of an Optical Nanosensor System for Mechanistic Analysis of a Novel Topoisomerase I Targeting Drug: A case story. Nanoscale 2016, 1886–1895, doi:10.1039/C6NR06848K.
  4. Pommier, Y. Topoisomerase I inhibitors: camptothecins and beyond. Nat. Rev. Cancer 2006, 6, 789–802, doi:10.1038/nrc1977.


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.