Heat Labile dsDNase (HL-dsDNase)
Double-strand specific DNase (dsDNase) is a unique double-strand specific endonuclease. As it does not digest ssDNA, it can be used to remove dsDNA in the presence of single stranded DNA molecules, such as primers and probes. dsDNase is heat-labile, which makes it ideal for applications where the DNase have to be inactivated.
The heat labile dsDNase can be heat inactivated by treatment at 55°C for 15 min. If proceeding directly to PCR, 55°C for 5 min is sufficient. The enzyme requires 1 mM DTT and pH > 8 for inactivation.
One unit is defined as an increase in absorbance at 260 nm of 0.001 per minute, using 50 mg/ml of high MW DNA in 50 mM Na-acetate pH 5.0 and 5 mM MgCl2.
HL-dsDNase is highly active in a temperature range of 20-40°C. It needs at least 2.5 mM Mg for activity and has an optimal pH at 7.5.
Minimum shelf life is 2 years at -20°C. Storage at 4°C is possible for at least 6 months. The enzyme also tolerates multiple freeze-thaw cycles.
HL-dsDNase is purified to apparent homogeneity.
Ca. 200 000 Kunitz Units/mg.