Trypsinogen is an enzyme released by the pancreas that is used to break down proteins found in foods. Before it reaches the digestive tract, the enzyme is inactive. Once it reaches the intestines, trypsinogen is converted to its active form, trypsin. Levels of this enzyme present in the bloodstream can be monitored to determine if there is a problem with pancreas function.
Proteases, such as trypsinogen, are enzymes that digest proteins. These molecules enter the intestines and break apart long chains of proteins into usable fragments of amino acids. Trypsinogen works on proteins in the arginine and lysine families, while other proteases focus on different types of proteins.
The pancreas creates proteases in an inactive form. Inert, these enzymes do not damage the pancreas on their way to the intestines. When the inactive enzyme trypsinogen reaches the small intestine, a part of the molecule is broken off, transforming the molecule into its active form, trypsin.
There are three varieties of trypsinogen that are produced by the pancreas. Cationic and anionic trypsinogen are the most common and account for most protein digestion. The third type of trypsinogen, called mesotrypsinogen, is highly resistant to protease inhibitors, which block the digestive action of various proteases. This type of trypsinogen is used to break down the proteins in foods, such as soy beans, that are rich in protease inhibitors.
Protease inhibitors are found in a variety of foods, especially in seeds. By producing a chemical that makes protease chemicals inactive, the seeds protect themselves from being digested. Though many seeds can be broken down, there are also many that pass through the digestive system undamaged. Certain types of bacteria and protozoa that live in the digestive tract also produce protease inhibitors.
A deficiency of trypsinogen in the blood can be an indicator of cystic fibrosis, which is a relatively uncommon genetic disorder. Newborn infants may be checked for this disease if they do not produce solid waste by the end of the second day after birth. Adults and older children may also be tested for trypsinogen levels if the pancreas does not appear to be functioning normally.
The body requires protein for a number of different functions, and though some of the protein needed can be manufactured, additional protein must be added into the system each day. Proteases make use of protein that is consumed in food. Once their job is done, they are rendered inert again, and the amino acid chains in the proteases are recycled as a source of protein.