DNase I is an endonuclease derived from bovine pancreas that will degrade double-stranded DNA in the presence of divalent cations producing 3”-OH oligonucleotides. Mg²+ in the reaction so ution auses the enzyme to produce
nicks in double-stranded DNA, while in the presence of Mn²+ DNase I cleaves both strands of the DNA. DNase I is useful in nick translation f or introducing single-stranded nicks that serve as primer sites for initiation of DNA synthesis
and for cloning random DNA fragments by cleaving double-stranded DNA. DNase I is a chromatographically pure preparation. It is offered as lyophilized powder. For greatest stability, it is important that DNAse be dissolved at a concentration
of at least 1mg/ml in 50% Glycerol with 20mM Tris-HCl, pH 7.5 and 1mM MgCl2.This solution can be stored at -20oC for at least a year.