zymogen

(noun)

A proenzyme, or enzyme precursor, which requires a biochemical change (i.e. hydrolysis) to become an active form of the enzyme.

Related Terms

Examples of zymogen in the following topics:

  • Chemical Digestion of Carbohydrates, Proteins, Lipids, and Nucleic Acids

    • The digestive enzymes, however, are secreted mainly as their inactive precursors, the zymogens.

  • Associated Organs

    • The pancreas synthesizes its enzymes in the inactive form, known as zymogens, to avoid digesting itself.
    • These zymogens are inactivated forms of trypsin and chymotrypsin.

  • Regulation of Water Intake

    • Renin cleaves the zymogen angiotensinogen, always present in plasma as a result of constitutive production in the liver, into a second inactive form, angiotensin I, which is then converted to its active form, angiotensin II, by angiotensin converting enzyme (ACE), which is widely-distributed in the small vessels of the body.