KROK 1 2023 – Question 149 · KROK (Medicine) · Biological Chemistry
Pepsin is the enzyme of gastric juice that is secreted in its inactive form of pepsinogen. What is the mechanism of its activation?
- A. Dephosphorylation
- B. Phosphorylation
- C. Limited proteolysis
- D. Methylation
- E. Acetylation
Hint
Pepsinogen is a zymogen; compare the reversible covalent modifications used to regulate intracellular enzymes with the kind of irreversible change that switches on a secreted digestive proenzyme in the acidic lumen.
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