Most digestion takes place in the mouth, stomach, duodenum, and the jejunum. Digestion enzymes help break down nutrients we get from food into smaller building blocks which the body can appropriately use. A large function of digestive enzymes is to ensure proper digestion of food as well as ensure proper function of cell metabolism. The salivary glands also secrete enzymes that aid in digestion during the beginning of the digestive process.
There are a few types of digestive enzymes. They are categorized by their substrates.
The digestive enzymes are secreted by these glands:
Digestion begins right in the mouth as food is chewed and covered up by saliva. The salivary glands in the oral cavity secrete Ptyalin, which is a digestive enzyme that helps digest starch into smaller sugars. Other digestive enzymes in that come from the salivary glands are
Stomach enzymes are called gastric enzymes.
The pancreas is actually the main digestive gland in our body. It secretes many enzymes such as:
The organs in the small intestine that secrete digestive enzymes are the jejunum and ileum. They secrete the following enzymes Sucrase, Maltase, Isomaltase and Lactase, which all break down sugars in different ways. An enzyme called Intestinal Lipase is also secreted and it helps breaks down fatty acids.
Enzymes are mainly proteins, that increase the rates of chemical reactions. Almost all processes in a biological cell need enzymes to occur at significant rates. The set of enzymes made in a cell determines which metabolic pathways occur in that cell.
Enzymes work by lowering the amount of energy needed for a reaction, thus dramatically increasing the rate of the reaction. Most enzyme reaction rates are millions of times faster than those of comparable un-catalyzed reactions. Enzymes are known to help speed up about 4,000 biochemical reactions.
Digestive Enzymes can be affected by other molecules. Inhibitors are molecules that decrease enzyme activity. Many drugs and poisons are enzyme inhibitors.
Like all proteins, enzymes are made as long, linear chains of amino acids.
Enzymes and Disease
Since the tight control of enzyme activity is essential for homeostasis, any malfunction (mutation, overproduction, underproduction or depletion) of a single critical enzyme can lead to a genetic disease. The importance of enzymes is shown by the fact that a lethal illness can be caused by the malfunction of just one type of enzyme out of the thousands of types present in our bodies.
Enzymes help the immune system function at its highest level. White blood cells contain digestive enzymes which are a necessary part of the pancreatic and digestive juices, which ultimately help in getting all the right nutrients out of the foods we eat. There are also other enzymes that help increase immune function.