Enteropeptidase or enterokinase is an enzyme involved in human digestion. It is produced by cells in the duodenum wall, and is secreted from duodenum's glands, the crypts of Lieberkühn, whenever ingested food enters the duodenum from the stomach. Enteropeptidase has the critical job of turning trypsinogen (a zymogen) to trypsin, indirectly activating a number of pancreatic digestive enzymes. Enteropeptidase is a serine protease enzyme (EC3.4.21.9). Enteropeptidase is a part of the Chymotrypsin-clan of serine proteases, and is structurally similar to these proteins. The light chain of enteropeptidase has full enzymatic activity. No other protease activity was detected.
Source:Recombinant protein corresponding to human Enterokinase, a specific protease that cleaves after the sequence Asp-Asp- Aps-Aps-Lys, expressed in E. coli.
Assay Conditions:50mM Tris-HCl or sodium phosphate, pH 8.0 with or without calcium chloride. The enzyme is active at a pH range of 6.0-9.0.
Unit Definition:One unit of human enteropeptidase will cleave 2mg of thioredoxin/human EGF fusion protein with the Asp-Asp-Asp-Asp-Lys sequence at the joining point in 22 hours at 4°C, in 16 hours at 25°C or in 8 hours at 37°C.
Storage and Stability:May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 6 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
仕様
Size：20IU
Source Antigen：Recombinant, E. coli
Grade：Molecular Biology Grade
Form：Supplied as a liquid in 50mM Tris-HCl, pH 8.0, 0.5M sodium chloride, 50% glycerol.
