Metabolism USMLE Step 1 Practice Question
A 34-year-old female presents to her physician complaining of oral ulcers. A careful history reveals that she is a strict vegetarian and does not eat meat, fish, poultry, eggs, or dairy products. She is found to have a severe riboflavin deficiency. The function of which of the following enzymes in the citric acid cycle would be most directly affected by the riboflavin deficiency?
Answer choices
- ACitrate synthase
- BMalate dehydrogenase
- CIsocitrate dehydrogenase
- DSuccinate dehydrogenaseCorrect answer
- EAconitase
- FFumarase
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