iron–porphyrin group

biochemistry

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June 29, 2026

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The iron-porphyrin group is a crucial component in biochemistry, primarily found in hemoproteins. These are complex molecules where a porphyrin ring, a cyclic structure made of four pyrrole rings, binds to a central iron atom. This iron-porphyrin complex is known as heme.123

Hemoproteins play vital roles in biological processes. Examples include chlorophyll, essential for photosynthesis in plants; hemoglobin, which transports oxygen in animal blood; and cytochromes, involved in cellular oxidation. The intense color of heme proteins, like hemoglobin, is due to the porphyrin structure, which absorbs light strongly around 410 nanometers.12

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circulatory system
Blood
…of subunits, each containing an iron–porphyrin group attached to a protein. The distribution of hemoglobins in just a few members of a phylum and in many different phyla argues that the hemoglobin type of molecule must have evolved many times with similar iron–porphyrin groups and different proteins.
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…of subunits, each containing an iron–porphyrin group attached to a protein. The distribution of hemoglobins in just a few members of a phylum and in many different phyla argues that the hemoglobin type of molecule must have evolved many times with similar iron–porphyrin groups and different proteins.
Read More