| enz | sec by | inactive form | activated by | opt PH | type | net result | |
| 1-stomach | |||||||
| pepsin | chief cells of gastric mucosa in an inactive form | pepsinogen | HCL or autoactivatn | 2-2.2 | it is an endopeptidase acting on central peptide linkage where amino gp is derived from aromatic AA | formatn of proteoses ,peptones ,few AA | |
| gastrin | central gastric mucosa | under stim of food | gast stim chief cells to sec pepsinogen & parietal cells to sec HCL for 1-denaturation of protein 2-act of pepsinogen 3-kill bacteria (N.B) ethanol stim >gastrin >stim HCL >peptic ulcer | ||||
| Rennin | in stomach of infants for milk clotting | in presence of Ca change casein to Ca para caseinate w is acter by pepsin | |||||
| 2-small intestine | |||||||
| 1-pancreatic juice (contain 2 endopeptidase and 2 exopeptidase) | |||||||
| Trypsin | trypsinogen | enterokinase then by auto activation | 5 to 9 | it is endopeptidase acting by central peptide linkage where amino gp is derived from basic AA | |||
| kymotrypsin | zymogen form | trypsin | 5 to 9 | endopeptidase acting on central peptide linkage where cooH gp is derived from aromatic AA | it is also a milk clotting enz | ||
| carboxy peptidases A& B | called erepsin | 7.4 | exopeptidases acting on terminal peptide linkage having free carboxyl gp | ||||
| 2-succus entericus from intestine itself | |||||||
| 1-Amino peptidase | exopeptidase acting on terminal peptide linkage having free amino gp | ||||||
| 2-Tripeptidases & dipeptidases | act on tripeptide & dipeptide and the net result of digestion of protein is AA | ||||||