Micrococcal nuclease is derived from Staphylococcus aureus and is a relatively non-specific endo-exonuclease

It is purified from a recombinant E. coli strain that digests double-stranded, single-stranded, circular and linear nucleic acids. The enzyme is active in the pH range of 7.0 - 10.0, with optimal activity at pH 9.2 for both RNA and DNA substrates. Cleavage preferences have been observed at sites rich in adenylate, deoxyadenylate or thymidylate. Both DNA and RNA are degraded to 3´ phosphomononucleotides and dinucleotides.