In heme synthesis in mammalian cells:
Uroporphyrin III is the immediate precursor of
d -aminolevulinic acid is formed by the condensation of
succinyl CoA and valine
Ferric iron is inserted into protoporphyrin IX
prior to attachment to the globin molecule
- D. Porphobilinogen is formed by the condensation of
two d-aminolevulinic acids
A, B and C
A and C
B and D
- D only
All of the above
- A. Neither compound is on the pathway of heme synthesis.
- B. Succinyl CoA condenses with glycine, not valine.
- C. It is iron (II), or ferrous iron, that is inserted.
- D. Correct. This is a dehydration reaction.
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