Cofactors, enzymes and prosthetic grouls

• What are cofactors in enzymatic reactions?

  Non-protein components needed for enzyme function
• How do cofactors assist enzymes?

  They transfer groups or form part of the active site
• What is a coenzyme?

  An organic molecule that acts as a cofactor
• How are inorganic cofactors obtained?

  Via the diet as minerals
• What is an example of a cofactor in amylase?

  A chloride ion
• Where do many cofactor coenzymes derive from?

  Vitamins found in the diet
• What vitamin is used to make coenzyme A?

  Vitamin B3
• What are prosthetic groups?

  Tightly bound cofactors required for enzyme function
• How do prosthetic groups differ from other cofactors?

  They are tightly bound and permanent
• What is a precursor enzyme?

  An inactive form of an enzyme
• Why are precursor enzymes produced in an inactive form?

  To prevent damage and control enzyme activity
• What is required for precursor enzymes to become active?

  A change in shape, often by a cofactor
• What is an apoenzyme?

  A precursor protein before cofactor addition
• What happens when a cofactor is added to an apoenzyme?

  It becomes an active holoenzyme
• How can the change in tertiary structure of a precursor enzyme occur?

  By the action of another enzyme cleaving bonds
• What are zymogens or proenzymes?

  Inactive precursor enzymes that require activation
• What triggers the activation of zymogens?

  Changes in tertiary structure under certain conditions