Recombinante Enterokinase datasheet

Recombinant Enterokinase
(Cat No.: E004)

Description:
    Recombinant Enterokinase (rEK) is the catalytic subunit of bovine enterokinase, which is expressed by the yeast Pichia pastoris and purified to yield a high enzyme activity preparation. rEK recognizes the sequence Asp-Asp-Asp-Asp-Lys and cleaves the peptide bond after the lysine residue. The enzyme can be used to cleave any fusion protein that carries this sequence. (Figure 1)

Figure 1-  Digestion of Thioredoxin-NP-27 fusion protein with rEK

                             Each reaction contains 15 µg of partially purified thioredoxin-NP-27 fusion protein and 
                       varying amounts of rEK. Reactions were incubated at 37^oC for 16 hours and analyzed on a
                       Coomassie-stained 15% SDS gel. Units of rEK used per reaction are list below.

Lane A: No rEK                 Lane E: 0.008 units
Lane B: 0.0008 units          Lane F: 0.015 units
Lane C: 0.0015 units          Lane G: 0.03 units
  Lane D: 0.003 units                                            

Unit Definition:
    One unit of rEK is the amount of enzyme required to digest 0.5mg of thioredoxin-NP-27 fusion protein to 90% completion in 16 hours at 37^oC.

Storage:
    rEK in 50 mM potassium phosphate, pH 8.0, 500 mM NaCl and 50% glycerol should be stored at -20^oC. Guaranteed stable for 1 year when stored properly.
 

10x Reaction Buffer:
    500 mM Tris-HCl, pH 8.0 (22^oC), 10 mM CaCl₂, 1% Tween-20.

    1. For 1 liter, dissolve 60.5 g Tris base in 950 ml deionized water.
    2. Adjust pH to 8.0 with concentrated HCl.
    3. Add 1.47 g CaCl₂-2H₂O and 10 ml Tween-20 and mix.
    4. Adjust the volume to 1 liter. Store at room temperature.