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  • Enterokinase, light chain

    Description

    Enterokinase is a specific protease that cleaves after lysine at its cleavage site Asp-Asp-Asp-Asp-Lys. It will sometimes cleave at other basic residues, depending on the conformation of the protein substrate. Enterokinase will not cleave at site followed by proline.

    Product Source

    This preparation is purified from k. lactis containing a clone of the light chain of the bovine enterokinase gene (1,2).

    Properties and Usage

    Unit Definition

    1 unit is defined as the amount of enzyme required to cleave 25 µg of a MBP-EK-paramyosin-ΔSal substrate to 95% completion in 16 hours at 25°C in a total reaction volume of 25 µl.

    Storage Temperature

    -20°C

    Storage Conditions

    20 mM Tris-HCl
    200 mM NaCl
    2 mM CaCl2
    50% Glycerol
    pH 7.2 @ 4°C

    Molecular Weights

    Apparent: 31 kDa
    Theoretical: 26.3 kDa

    Unit Assay Conditions

    Two fold dilutions of Enterokinase, light chain are incubated with 25 µg MBP-EK-paramyosin-ΔSal substrate in 20 mM Tris-HCl, 50 mM NaCl, 2 mM CaCl2 (pH 8.0 @ 25°C) in a 25 µl reaction. The reaction mix is incubated at 25°C for 16 hours. Separation of reaction products are visualized by SDS-PAGE.

    Notes

    1. CaCl2 is essential for proper activity as Enterokinase is a calcium dependent protease.
    2. NaCl concentration above 50 mM will significantly inhibit enzyme activity.
    3. Removal: Enterokinase will bind specifically to trypsin inhibitor agarose (e.g., Sigma T-0637).
    4. Enterokinase is a glycosylated protein.

    References

    1. Collins-Racie, L.A. et al (1995). Biotechnology. 13, 982-987.
    2. Taron, C. and Colussi, P. Unpublished observation

    Datacards

    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.

    Selection Charts

    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]

    Specifications

    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.

    Datacards

    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.