Endonucleases DNA-specific

Double-Strand Specific dsDNase (dsDNase) is ideal for fast and effective removal of contaminating DNA from PCR master mixes.

Taq polymerases are commonly contaminated by bacterial DNA. This is a problem in PCR based bacterial typing and detection as it might cause false positive results. The unique properties of dsDNase make it suited for removal of contaminating DNA from PCR master mixes prior to addition of DNA template.

In figure 1, a PCR master mix was treated with different amounts of dsDNase before performing a qPCR to measure the contaminating bacterial DNA in the master mix. ArcticZymes dsDNase effectively removed contaminating DNA below known levels of the assay detection limits.

The dsDNase from an Arctic source is recombinantly produced in Pichia pastoris. It cleaves phosphodiester linkages in DNA, to yield oligonucleotides with 5′-phosphate and 3’-hydroxyl termini.

The specific activity is estimated to be 30 times higher than that of bovine DNase I. In the presence of magnesium as only divalent cation and using oligos as a substrate, the activity towards dsDNA is 5000-fold higher than towards ssDNA.

The unique double strand-specificity allows specific degradation of dsDNA while leaving shorter ssDNA as primers and probes essentially intact. Easy inactivation by moderate heat (65°C) allows addition of DNA intended for analysis directly after removal of contaminating DNA.

Workflow – Decontamination of PCR master mixes

Recommended applications:

• Decontamination of PCR master mixes
• Removal of genomic DNA from RNA preparations

Key advantages with dsDNase:

• Double-strand DNA specific endonuclease
• High specific activity
• Can be heat-inactivated by moderate heat treatment (65°C for 15 minutes)
• Producing 5′-phospho-oligonucleotide products