KROK 1 2018 – Question 34 · KROK (Medicine) · Biological Chemistry
A 42-year-old man with gout presents with high content of uric acid in blood. The patient was prescribed allopurinol to lower the concentration of uric acid. Allopurinol is a competitive inhibitor of the following enzyme:
- A. Guanine deaminase
- B. Adenosine deaminase
- C. Hypoxanthine phosphoribosyltransferase
- D. Xanthine oxidase
- E. Adenine phosphoribosyltransferase
Hint
Trace the final steps by which purine bases are oxidised to uric acid and decide which enzyme a structural analogue of a purine base would compete for.
The answer, the explanation and a note on every option are available once you log in. The account is free: topic tests, a mock exam, mistake review and statistics.
More questions on Biological Chemistry
- Nitrogen is being excreted from the body mainly as urea. When activity of a certain enzyme in the liver is low, it results in inhibition of urea…
- People, who for a long time remained in hypodynamic state, develop intense pain in the muscles after a physical exertion. What is the most likely…
- A patient suffers from hepatic cirrhosis. What substance excreted in urine should be analyzed to characterize the antitoxic function of liver?
- Blood of the patients with diabetes mellitus shows increased content of free fatty acids. Name the most likely cause of this:
- Patients with bile duct obstruction typically present with inhibited blood clotting and develop hemorrhages due to insufficient assimilation of…
- During intensive muscle work there is a large amount of ammonia produced in the muscles. What amino acid plays the main role in the transportation…