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This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages) This article is an orphan, as no other articles link to it. Please introduce links to this page from related articles; try the Find link tool for suggestions. (March 2011) This article possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (April 2009) (Learn how and when to remove this message) This article does not cite any sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Steapsin" – news · newspapers · books · scholar · JSTOR (October 2017) (Learn how and when to remove this message) (Learn how and when to remove this message)

Steapsin belongs to the class of digestive enzymes called lipases found in the pancreatic juice that catalyzes the hydrolysis of triglycerides (main constituent in vegetable oils and animal fat) to fatty acids and glycerol. When food travels through the oral cavity and down the esophagus into the stomach, enzymes such as pepsin are released where it cleaves large proteins into smaller peptide fragments so further digestion and absorption can occur in the duodenum, the first part of the small intestine. Fats are minimally digested in the stomach by gastric lipases but most digestion occurs in the small intestine.

Function

The lipase steapsin is secreted from the pancreas to break down triglycerides to liberate the fatty acids and glycerol. The free fatty acids can then be absorbed to the liver and kidneys where it may be converted to glyceraldehyde 3-phosphate, a constituent in the process of glycolysis to ultimately generate energy in the form of ATP via the citric acid cycle. Fatty acids that are not used for energy can then be allowed to cross the intestinal barrier to be repackaged into fatty tissue.

Inhibitors

Trypsin

Trypsin, a protease, functions as a steapsin inhibitor. Trypsin is produced in the pancreas and secreted as trypsinogen, an inactive precursor of trypsin. The reason for this is to prevent trypsin from acting upon the pancreas. Upon entering the duodenum, enteropeptidase is secreted which activates trypsin. Trypsin reduces steapsin activity in the gastric tract by digesting it (proteolysis).

Anti-inhibitors

Egg Albumen

Egg albumen or egg whites acts as a trypsin inhibitor because egg whites are full of protein which allows trypsin to act upon the egg whites instead of steapsin. This allows the trypsin to be neutralized and allows steapsin's activity to remain unchanged.

References

• Orphaned articles from March 2011
• Hydrolases