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  • Micrococcal Nuclease

    recombinant unique buffer incubation temp heat inactivation no
    Catalog #SizeConcentrationPriceQtyAdd to Cart
    M0247S320,000 gel units2,000,000 gels units/ml$69.00Add to Cart
    Nuclease Products


    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 (1). Both DNA and RNA are degraded to 3´ phosphomononucleotides and dinucleotides.

    Micrococcal Nuclease works well with the SimpleChIP™ Enzymatic Chromatin IP Kit (Agarose Beads) #9002 from Cell Signaling Technology. Please follow the link to see product information and protocols on their website.

    Figure 1: Digestion of 1 µg of Lambda genomic DNA with Micrococcal Nuclease in a 3-fold dilution series. The amount of enzyme used in Lane 2 is defined as 1 gel unit. Lane M is the PCR Marker (NEB #N3234).


    • Can be used for Chromatin Studies
    • Inactive until Ca2+ is added

    Product Source

    An E. coli strain containing a genetic fusion of the micrococcal nuclease gene (Gene ID: 3238436) and the gene coding for maltose binding protein, or MBP. The micrococcal nuclease is cleaved from the fusion protein and purified away from MBP.

    Reagents Supplied

    The following reagents are supplied with this product:

    Store at (°C)Concentration
    Micrococcal Nuclease Buffer10X
    BSA-2010 mg/ml

    Advantages and Features


    • Degrade nucleic acids present in protein preparations
    • In vitro translation (2)
    • Reduce the viscosity of cell lysates during non-mechanic cell lysis preparation
    • Chromatic structure analysis (3)
    • Rapid RNA sequencing

    Properties and Usage

    Unit Definition

    (Kunitz Unit) One unit is defined as the amount of enzyme required to release acid soluble oligonucleotides that produce an absorbance increase of O.D. 1.0 at 260 nm in 30 minutes at 37°C. 

    (Agarose Gel Unit) One gel unit is defined as the amount of enzyme required to digest 1 µg of lambda genomic DNA in 15 minutes at 37°C, to the extent that the accumulation of low molecular DNA fragments (100-400 base pairs) disappears on a 1.2% agarose gel. 

    Note: 10,000 Gel Units is approximately equal to 1,000 Kunitz Units.

    Reaction Conditions

    1X Micrococcal Nuclease Reaction Buffer
    Incubate at 37°C

    Storage Temperature


    Storage Conditions

    10 mM Tris-HCl
    50 mM NaCl
    1 mM EDTA
    50% Glycerol
    pH 7.5 @ 25°C

    Heat Inactivation


    Unit Assay Conditions

    (Kunitz Unit) 1X Micrococcal Nuclease Buffer, 0.1mg/ml BSA and 500 µg sonicated Salmon testis genomic DNA in a total volume of 500 µl. 

    (Agarose Gel Unit) 1X Micrococcal Nuclease Buffer, 0.1mg/ml BSA and 1 µg of Lambda genomic DNA in a total volume of 50 µl.

    Quality Control

    Quality Assurance Statement

    • Free of detectable protease activity.


    1. This enzyme does not work in NEBuffer 1, 2, 3 or 4 due to the lack of Ca2+. Additional Ca2+ in NEBuffer only shows 10% activity. 1-5 mM Ca2+ is required for activity.
    2. The enzyme is active in the pH range 7-10 as long as salt concentration is less than 100 mM.
    3. Enzyme can be inactivated by addition of excess EGTA.


    1. Cuatrecasas, S.F., and Anfinsen, C.B. (1967). J. Biol. Chem. 244, 1541-1547.
    2. Craig, D. et al. (1992). Nucl. Acids Res. 20, 4957-4987.
    3. O'Neill, L.P. and Turner B.M. (2003). Methods. 31, 76-82.

    Supporting Documents

    Material Safety Datasheets

    The following is a list of Material Safety Data Sheets (MSDS) that apply to this product to help you use it safely. The following file naming structure is used to name these document files: [Product Name] MSDS. For international versions please contact us at info@neb.com.


    The Product Summary Sheet, or Data Card, includes details for how to use the product, as well as details of its formulation and quality controls. The following file naming structure is used to name the majority of these document files: [Catalog Number]Datasheet-Lot[Lot Number]. For those product lots not listed below, please contact NEB at info@neb.com or fill out the Technical Support Form for appropriate document.
    1. Will Micrococcal Nuclease cleave DNA as well as RNA and what type of end is left after digestion?
    2. Does Micrococcal Nuclease work in ChIP sequencing protocols?

    Selection Tools

    Addition of 1-5 mM Ca++ will increase activity if there is any EDTA or EGTA present
    Addition of 1-5 mM EDTA or EGTA will chelate Ca++ and substantially decrease activity
    Enzyme inhibited by higher than 100 mM NaCl
    Used for chromatin structure analysis (CHiP)