Metabolism USMLE Step 1 Practice Question
An X-linked genetic disease affects a cation-transporting P-type ATPase, resulting in accumulation of copper in the intestinal epithelium because of failure to transport it normally into the blood. Infants with this disease have only 10% of normal blood copper levels. Decreased activity of which of the following enzymes is most likely to be identified in these infants?
Answer choices
- Aγ-Glutamyl carboxylase
- BProlyl hydroxylase
- CCytochrome aa3
- DTyrosinase
- ELysyl oxidaseCorrect answer
- FCeruloplasmin
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