Metabolism USMLE Step 1 Practice Question
A 26-year-old African American man comes to the physician because of a 3-day history of fatigue, back pain, and dark urine. One week ago, he developed a headache and was treated with aspirin. He does not smoke or use illicit drugs. Physical examination shows conjunctival pallor. A peripheral blood smear shows erythrocytes with inclusions of denatured hemoglobin. Which of the following enzymes is essential for the production of nucleotides in this patient?
Answer choices
- APyruvate carboxylase
- BCarbamoyl phosphate synthetase I
- CEnolase
- DGlucose-6-phosphatase
- ETransketolaseCorrect answer
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