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  • RsrII


    Product Source

    An E. coli strain that carries the RsrII gene from Rhodopseudomonas sphaeroides (S. Kaplan).

    Reagents Supplied

    The following reagents are supplied with this product:

    Store at (°C)Concentration
    CutSmart® Buffer-2010X

    Properties and Usage

    Unit Definition

    One unit is defined as the amount of enzyme required to digest 1 µg of λ DNA in 1 hour at 37°C in a total reaction volume of 50 µl.

    Reaction Conditions

    1X CutSmart® Buffer
    Incubate at 37°C

    1X CutSmart® Buffer:
    50 mM Potassium Acetate
    20 mM Tris-acetate
    10 mM Magnesium Acetate
    100 μg/ml BSA
    pH 7.9 @ 25°C

    Activity in NEBuffers

    NEBuffer 1.1: 25%
    NEBuffer 2.1: 75%
    NEBuffer 3.1: 10%
    CutSmart® Buffer: 100%

    Diluent Compatibility

    Storage Temperature


    Storage Conditions

    10 mM Tris-HCl
    250 mM NaCl
    1 mM DTT
    0.1 mM EDTA
    200 μg/ml BSA
    50% Glycerol
    0.15% Triton® X-100
    pH 7.4 @ 25°C

    Heat Inactivation

    65°C for 20 min

    Methylation Sensitivity

    dam methylation: Not Sensitive
    dcm methylation: Not Sensitive
    CpG Methylation: Blocked


    1. RsrII requires two copies of its recognition sequence for efficient cleavage to occur. If a DNA molecule (plasmid or linear) has only one copy of this recognition site, RsrII cannot digest it to completion. These two copies of recognition sites should ideally be on the same molecule to achieve 100% cleavage, however, two different molecules can be used with slightly less efficiency. For more information and recommendations on working with enzymes requiring multi-sites such as RsrII, please visit Restriction Enzyme Cleavage: ‘single-site’ enzymes and ‘multi-site’ enzymes


    1. Do degenerate recognition sites need to be palindromic?
    2. What effect does BSA have on the performance of NEB’s restriction enzymes when included in the new buffers?
    3. How can I access the old NEBuffer Activity Chart?
    4. I tested your restriction enzyme on the substrate DNA recommended by NEB, and it appears to be active, however it does not digest my DNA. What could be the reason?
    5. Why do I see a DNA smear on an agarose gel after a restriction digest?
    6. Why do I see additional DNA bands on my gel after a restriction digest?
    7. Why is my Restriction Enzyme not cutting DNA?
    8. How many nucleotides do I have to add adjacent to the RE recognition site in order to get efficient cutting?

    Tech Tips

    This enzyme may lose activity over time. The presence of DTT is important to retain good activity.
    If the activity is low, spike with DTT: 1 ul of 1M DTT to a 50 ul is ample.


    1. Optimizing Restriction Endonuclease Reactions
    2. Double Digest Protocol with Standard Restriction Enzymes

    Selection Charts

    Usage Guidelines & Tips

    Troubleshooting Guides

    Interactive Tools

    Certificate of Analysis

    The Certificate of Analysis (COA) is a signed document that includes the storage temperature, expiration date and quality control's for an individual lot. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]_[Lot Number]


    The Specification sheet is a document that includes the storage temperature, shelf life and the specifications designated for the product. The following file naming structure is used to name these document files: [Product Number]_[Size]_[Version]

    Safety Data Sheet

    The following is a list of Safety Data Sheet (SDS) that apply to this product to help you use it safely.