Pancreatic proteases

The digestive enzymes chymotrypsin, trypsin, and elastase areproduced as zymogens in the pancreas they are then transported  to the little intestine  as  their  zymogen  forms  and  activated  there  through  cleavage  of  specific peptide bonds. The Trypsin is synthesized initially as the zymogen trypsinogen.  It is cleaved and thus activated in the intestine through the enzyme enteropeptidase that is only produced in the intestine. At once it is activated; trypsin can cleave and activate further trypsinogen   molecules   as well as other zymogens,   like as proelastase and chymotrypsinogen. As well as secreting the zymogens and synthesizing the pancreas also synthesizes a small trypsininhibitor protein. This inhibitor protein connects very tightly to the active site of trypsin preventing the pancreas from being smashed through prematurely   activated trypsin molecules if  this  safety  mechanism   fails  for instance,  because  of a blocked  pancreatic  duct the zymogens  can become  activated and literally digest the pancreas a condition known as acute pancreatitis.

                      Figure:  The central role of trypsin in activating the pancreatic zymogens.