Shrimp DNase is an endonuclease that cleaves phosphodiester linkages in DNA to yield di- and oligonucleotides with 5’-phosphate and 3’-hydroxyl termini. This DNase has a remarkably high specific activity towards double-stranded DNA (dsDNA). The activity towards dsDNA is 5000-fold higher than towards single-stranded DNA, and thus can be used selectively to degrade dsDNA, leaving single-stranded DNA intact. The activity of this enzyme depends on Mg²⁺ concentration and is stimulated by Ca²⁺. However, Ca²⁺ also stimulates the RNase activity of shrimp DNase and should be avoided when RNA integrity is critical.

Source: Pichia pastoris strain containing overproducing clone of Pandalus borealis DNase.

Applications:
Selective degradation of dsDNA leaving ssDNA and RNA intact
Removal of DNA from RNA prior to RT-PCR
Removal of DNA template after in vitro transcription
Nick translation with DNA Polymerase I
Footprint determination of DNA binding protein
Used in removal of carryover contaminants in PCR

The DNase activity favours low ionic strength. Activity decreases with increasing ionic strength. This recombinant enzyme can be heat-inactivated by a moderate heat treatment without the use of EDTA. Shrimp DNase is totally inactivated at 70 °C after a 25 to 30 minute incubation.