Page 26 - Clinical biochemistry

Biosynthesis of heme

• Heme is an iron porphyrin structure, synthesized in the reticuloendothelial
cells (bone marrow) of adult human being.

• Porphyrin is converted to heme by addition of iron and then to hemoglobin
by addition of protein, globin. The type of porphyrin present in heme is
protoporphyrin-III (also known as No. IX).

• It is synthesized starting from glycine and succinyl-CoA. where ‘A’ stands
for acetyl group, ‘P’ stands for propyl group, ‘M’ for methyl group, and ‘V’
for venyl group.

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