ZYMOGEN
Zymogen is an enzyme's inactive precursor, sometimes known as a proenzyme. To become an active enzyme, zymogen must undergo a chemical transformation. Inactive precursors or zymogen undergo conformational modifications as a result of specific cleavage, exposing the enzyme active site.
Many proteolytic enzymes like chymotrypsin , trypsin are initially synthesized as inactive precursor chymotrypsinogen and trypsinogen.
Enteropeptidase and trypsin transform pancreatic zymogens such as chymotrypsinogen, trypsinogen, proelastase, and procarboxypeptidase into active enzymes such as chemotrypsin, trypsin, elastase, and carboxypeptidase.