Search results
Results from the WOW.Com Content Network
Pepsin / ˈ p ɛ p s ɪ n / is an endopeptidase that breaks down proteins into smaller peptides and amino acids.It is one of the main digestive enzymes in the digestive systems of humans and many other animals, where it helps digest the proteins in food.
The proenzyme Pepsinogen, with the exposure to hydrochloric acid gets converted into the active enzyme pepsin, the proteolytic enzyme of the stomach. Hydrochloric acid (HCl) provides the acidic pH (pH 1.8) optimal for pepsins. Rennin is a proteolytic enzyme found in gastric juice of infants which helps in the digestion of milk proteins.
It is produced in the stomach by gastric chief cells in its inactive form pepsinogen, which is a zymogen. Pepsinogen is then activated by the stomach acid into its active form, pepsin. Pepsin breaks down the protein in the food into smaller particles, such as peptide fragments and amino acids.
This produces a bolus which is swallowed down the esophagus to enter the stomach. The second stage, the gastric phase, happens in the stomach. Here, the food is further broken down by mixing with gastric acid until it passes into the duodenum, the first part of the small intestine. The third stage, the intestinal phase, begins in the duodenum.
The arrangement of these proteins on the apical and basolateral sides of the epithelium determines the net movement of ions and water in the tract. H + and Cl − are secreted by the parietal cells into the lumen of the stomach creating acidic conditions with a low pH of 1. H + is pumped into the stomach by exchanging it with K +.
Chronic inflammatory diseases such as rheumatoid arthritis may involve the release of lysosomal enzymes into extracellular space that break down surrounding tissues. Abnormal proteolysis may result in age-related neurological diseases such as Alzheimer 's due to the generation and ineffective removal of peptides that aggregate in cells.
The cud is then regurgitated, chewed slowly to completely mix it with saliva and to break down the particle size. Fibre, especially cellulose and hemi-cellulose, is primarily broken down into the volatile fatty acids, acetic acid, propionic acid and butyric acid in these chambers (the reticulo-rumen) by microbes: (bacteria, protozoa, and fungi ...
They can also be converted into glucose. [4] This glucose can then be converted to triglycerides and stored in fat cells. [5] Proteins can be broken down by enzymes known as peptidases or can break down as a result of denaturation. Proteins can denature in environmental conditions the protein is not made for. [6]