discuss zymogen activation to enzymes?

Question

discuss zymogen activation to enzymes?

Answer 1

A zymogen is an enzyme that is released in an inactive form, to prevent inapproprate activity, and must be activated through change in its structural conformation, usually by a change in pH, or through the action of antoher enzyme.

A prominent example of this is pepsinogen, a zymogen released by chief cells in the stomach. It is inactive until the acidic pH of hydrochloric acid released by parietal cells of the stomach activate pepsinogen to pepsin (which digests many proteins) -- the purpose of this is to prevent pepsin's digestive activity at other sites in the body, which would clearly be harmful. Thus, pH-dependence strictly limits its activity to the stomach, and thereby protects other organs.

Answer 2

A zymogen or a proenzyme, is an inactive enzyme precursor. A zymogen requires a biochemical change (such as a hydrolysis reaction revealing the active site, or changing the configuration to reveal the active site) for it to become an active enzyme. The biochemical change usually occurs in a lysosome where a specific part of the precursor enzyme is cleaved in order to activate it. The amino acid chain that is released upon activation is called the activation peptide.

Examples of zymogens are trypsinogen, chymotrypsinogen, pepsinogenand most of the proteins of the coagulation system,