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  • Nuclease BAL-31

    unique buffer heat inactivation
    Catalog #SizeConcentrationPriceQtyAdd to Cart
    M0213S50 units1,000 units/ml$62.00Add to Cart
    M0213L250 units1,000 units/ml$248.00Add to Cart
    Nuclease Products


    Nuclease BAL-31 exonuclease degrades both 3' and 5' termini of duplex DNA without generating internal scissions. The enzyme is also a highly specific single-stranded endonuclease which cleaves at nicks, gaps and single-stranded regions of duplex DNA and RNA (1,2).
    Ligation of Nuclease BAL-31 treated fragments
    A) Gel electrophoresis of Lambda DNA-HaeIII digest.  
    B) Lambda DNA-HaeIII digest after 2 minute incubation with one unit of Nuclease BAL-31. 
    C) As in (B) followed by incubation with T4 DNA Ligase.


    Progressive shortening of duplex DNA
    Inactivation by treatment with EGTA
    Supplied with 2X Reaction Buffer

    Product Source

    Purified from the culture medium of Alteromonas espejiana BAL-31. Contains a mixture of "fast" and "slow" species of the enzyme (3).

    Reagents Supplied

    The following reagents are supplied with this product:

    Store at (°C)Concentration
    Nuclease BAL-31 Reaction Buffer-202X

    Advantages and Features


    • Progressive shortening of double-stranded DNA fragments at both termini (4)
    • Restriction site mapping (2)

    Properties and Usage

    Unit Definition

    One unit is defined as the amount of enzyme required to remove 200 base pairs from each end of linearized double-stranded ΦX174 DNA (40 µg/ml) in a total reaction volume of 50 μl in 10 minutes at 30°C in 1X Nuclease BAL-31 Reaction Buffer.

    Reaction Conditions

    1X Nuclease BAL-31 Reaction Buffer
    Incubate at 30°C

    1X Nuclease BAL-31 Reaction Buffer:
    20 mM Tris-HCl
    600 mM NaCl
    12 mM MgCl2
    12 mM CaCl2
    1 mM EDTA
    pH 8 @ 25°C

    Storage Temperature


    Storage Conditions

    0.25 mM EDTA
    10 mM Tris-HCl
    50 mM NaCl
    1.5 mM CaCl2
    1.5 mM MgCl2
    200 μg/ml BSA
    50% Glycerol
    pH 8.0 @ 25°C

    Heat Inactivation

    65°C for 10 min

    Quality Control

    Quality Assurance Statement

    • Purified free of detectable double-stranded endonuclease activity.


    1. Duplex products of the exonuclease are a mixture of blunt and staggered ends. This mixture can be cloned directly, although maximal ligation efficiency requires repairing the staggered ends with a suitable DNA polymerase.
    2. If necessary, the enzyme may be diluted in reaction buffer prior to use.
    3. Activity is linear with enzyme concentration.
    4. Heat Inactivation will only work in the presence of 20mM EGTA.


    1. Gray, H.B. et al. (1975). Nucl. Acids Res.. 2, 1459-1492.
    2. Legerski, R.J. et al. (1978). Nucl. Acids Res.. 5, 1445-1463.
    3. Wei, C.-F. et al. (1983). J. Biol. Chem.. 258, 13506-13512.
    4. Sambrook, J., Fritsch, E.F. and Maniatis, T. (1989). Molecular Cloning: A Laboratory Manual (2nd Ed.). 5.73-5.75.

    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. Can Nuclease BAL-31 be used to remove 10 base pairs from the end of a DNA fragment?
    2. Why does all of the DNA get degraded when I use Nuclease BAL-31?
    3. Can Nuclease BAL-31 be heat inactivated?
    4. Is Nuclease BAL-31 active in other NEBuffers?
    5. Can Nuclease BAL-31 treated DNA be cloned?
    6. What is a good control for the BAL-31 nuclease?
    7. Will Nuclease BAL-31 degrade RNA?

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