dsDNase

dsDNase is a heat-labile endonuclease that has a strong preference for double-stranded DNA. dsDNase can be heat inactivated by heat treatment at 15 min at 65˚C, or 20 min at 60˚C. The enzyme requires 1 mM DTT and pH ≥ 8 for complete inactivation.

This dsDNase is a useful tool to remove contaminating DNA from PCR mastermixes.

• This nuclease has double-stand specificity, which allows specific degradation of dsDNA while leaving shorter ssDNA as primers.
• Easy inactivation by moderate heat (65°C) allows addition of DNA intended for analysis directly after removal of contaminating DNA.
• The specific activity is estimated to be 30 times higher than that of bovine DNase I.

Activity towards dsDNA is 5000-fold higher than towards ssDNA

In solution.

One Unit is defined as an increase in absorbance at 260 nm of 0.001 per minute, using 50 µg/ml high MW DNA in 100 mM Na-acetate pH 5.0 and 5 mM MgCl₂.

The 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.