(Cat No.: E004)
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
reaction contains 15 µg of partially
purified thioredoxin-NP-27 fusion
of rEK. Reactions were incubated at 37oC
for 16 hours and analyzed on a
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:
Lane C: 0.0015 units Lane G:
Lane D: 0.003
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
rEK in 50 mM potassium phosphate, pH
8.0, 500 mM NaCl and 50% glycerol should
be stored at -20oC.
Guaranteed stable for 1 year when stored
10x Reaction Buffer:
500 mM Tris-HCl, pH 8.0 (22oC),
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
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.