Recombinant Bovine Enterokinase ( rb-EK)

Enterokinase is a serine protease that can specifically cleave the sequence A sp-Asp-Asp-Asp-Lys after the lysine residue. It is commonly used for digesting fusion proteins to release the fusion partner or protein tag from the target protein. Native enterokinase is composed of a 115 kDa heavy chain membrane anchor and a 35 kDa light chain catalytic subunit. Recombinant Bovine Enterokinase (rb-EK) consists only of the catalytic subunit of the holoenzyme. This subunit is expressed and purified from E.coli, yielding an enzyme with a higher specific activity compared to the native protein.
 
Applications
Digestion of fusion proteins to release the fusion partner or protein tag from the target protein.
 
Synonyms
Enteropeptidase, ENTK, PRSS7
 
Activity
≥40 KU/mg
 
Theoretical pI
5.20
 
Formulation
Lyophilized from 5 mM PB, pH7.4
 
Molecular Weight
26.2 kDa, 30 kDa by SDS-PAGE analysis
 
Purity
≥95% by SDS-PAGE analysis
 
Endotoxin
≤5 EU/mg
 
Source
Escherichia coli.
 
Storage Condition
-20ºC
 
Storage Duration
3 years
 
Unit Definition
1 unit is defined as the amount of rb-EK that will digest 50 μg of 1 mg/mL fusion protein to 95% completion in 16 hours at 25ºC in 50 mM Tris-HCl, pH 8.0.
 
Notes
Rb-EK is known to be inhibited by >2 M Urea, >250 mM NaCl, >20 mM βME, >0.1% SDS, or >50 mM imidazole. Dialyze your fusion protein to remove the inhibitors prior to digestion with rb-EK
Avoid using phosphate buffers
 
SKU: RBEK400, RBEK4000