Micrococcal nuclease or MNase is a 16.9 kDa endonuclease derived from Staphylococcus aureus. It is purified from an E. coli strain expressing an N-terminal 6XHIS tagged micrococcal nuclease.
Purified protein exhibit an strong endonuclease activity against single-stranded, double-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.
The rate of cleavage is 30 times greater at the 5’ side of A or T than at G or C and results in the production of mononucleotides and oligonucleotides with terminal 3’-phosphates.
MNase is suitable for removing nucleic acids from cell lysates, releasing chromatin-bound proteins and shearing chromatin for use in chromatin immunoprecipitation (ChIP) experiments.