Topoisomerase I, Recombinant, Human, His-Tag (DNA Topoisomerase-I, TOP1, TOP-I, Topoisomerase (DNA) I, Topoisomerase 1, Topoisomerase1, Topoisomerase-1, Topoisomerase-I, Type I DNA Topoisomerase)

Blue Ice

91, 57

Supplied as a liquid in 16mM HEPES, pH 8.0, 250mM sodium chloride, 20% glycerol.

DNA toposisomerase I is a key nuclear enzyme that interconverts supercoiled DNA to the required topological conformations for normal DNA replication and transcription. This enzyme is the target antigen for the so-called Scl-70 autoantibodies. Scl-70 antibodies are a specific marker in Scleroderma patients (specificity 98-100%) and are associated with the presence of diffuse skin involvement and pulmonary fibrosis. In human tissues the DNA topoisomerase I is initially synthesized as a protein with 100kD molecular weight. Most of this precursor is then proteolytically processed to a species with 70kD molecular weight from which the Scl-70 antigen has derived its name.

Recombinant protein corresponding to human TOP1, fused with a 6xHis-tag, expressed in Sf9 insect cells.

Molecular Weight:
~91.57kD

Specificity:
Binds IgG-type human auto-antibodies.

Applications:
Suitable for use in ELISA, Western Blot, Biotinylation and Iodination. Other applications not tested.

Recommended Dilution:
ELISA: 0.5-0.8ug/ml, (depending on the type of ELISA plate and coating buffer). Standard ELISA test: (checker-board analysis of positive/negative sera panels including CDC international reference sera).
Western Blot: with monoclonal anti-hexa-His-tag antibody and Scleroderma patient sera.
Optimal dilutions to be determined by the researcher.

Storage and Stability:
May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.