Trypsin-2, also known as Trypsin II, Anionic trypsinogen, Serine protease 2, PRSS2 and TRY2, is a secreted protein which belongs to the trypsin serine protease family including Trypsin, PRSS1, PRSS2 and PRSS3. It consists of a signal peptide (residues 1-15), a pro region (residues 16-23), and a proteolytically active mature chain (residues 24-247). PRSS2 contains one peptidase S1 domain. It is secreted into the duodenum, hydrolysing peptides into their smaller building blocks, which is necessary for the uptake of protein in the food. It is secreted by the pancreas in the form of inactive zymogen, trypsinogen and cleaved to its active form in the small intestine when the pancreas is stimulated by cholecystokinin through the common activation mechanism.