BIOCHEMISTRY - Textbook - Ostapchenko L. I. - 2012

Chapter 6. AMINO ACID METABOLISM AND FUNCTIONS. PROTEIN BIOSYNTHESIS

6.3. Protein Digestion

6.3.3. Cellular Protection against Protease Action

Pancreatic Cells are protected from the action of digestive Enzymes because:

✵ these enzymes are synthesized as inactive precursors within the pancreatic cells and are activated only upon secretion into the intestinal lumen. Consequently, the site of synthesis and The Site of Action of these enzymes are spatially separated;

✵ pancreatic cells contain a Trypsin inhibitor protein that forms a stable complex with the active form of the enzyme (in the event of premature activation).

In the gastric and intestinal cavities, proteases do not come into contact with cellular Proteins because the mucosa is covered with a layer of mucus, while the outer surface of Cell/30.html">The Plasma Membrane of each cell contains Polysaccharides that are resistant to protease Digestion, thereby protecting The Cell from their action.

The degradation of cellular proteins by proteases occurs during PEPTIC ULCER DISEASE or duodenal ulcers. However, the initial mechanisms underlying The Development of ulcers remain insufficiently understood.



Last update: 06/08/2026

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