Enterokinase (EC 3.4.21.9) is a serine protease involved in the activation of trypsinogen to trypsin, which in turn results in the activation of various digestive enzymes. It recognizes a highly specific amino acid sequence `DDDDK' and cleaves after the lysine residue. High specific activity of enterokinase has been utilized in cleaving a variety of native or fusion protein tags containing the above recognition motif. MW: 26.3 kDa. Purity ≥90%