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?

  1. A)Pyruvate carboxylase
  2. B)Carbamoyl phosphate synthetase I
  3. C)Enolase
  4. D)Glucose-6-phosphatase
  5. E)TransketolaseGABARITO

Explicação

This patient has G6PD deficiency (African American, hemolysis after aspirin, Heinz bodies on smear). G6PD catalyzes the rate-limiting step of the pentose phosphate pathway (PPP) oxidative branch, which normally produces ribose-5-phosphate (R5P) for nucleotide ... Ver explicação completa e trilha adaptativa →

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