Pepsin (EC 3.4.23.1) is a peptidase A1 family aspartic protease that serves as a primary digestive enzyme in the mammalian stomach. Pepsin is synthesized in the chief cells of the gastric mucosa as the inactive pro-enzyme pepsinogen, which contains a 44 amino acid autoinhibitory domain. The proenzyme is packaged into granules and stored inside the gastric mucosal cells. When food is consumed, neuronal signals traveling along the vagus nerve trigger secretion of HCl and pepsinogen into the stomach. In the highly acidic environment of the stomach, pepsinogen unfolds and undergoes autocatalytic cleavage, forming the active protease pepsin. Infection by the bacterium H. pylori induces hypersecretion of both stomach acid and pepsin, contributing
Size
100 assays
Concentration
n/a
Applications
Estimation of pepsin activity in various biological samples