Chromoprotein

A chromoprotein is a conjugated protein that contains a pigmented prosthetic group (or cofactor). A common example is hemoglobin, which contains a heme cofactor, which is the iron-containing molecule that makes oxygenated blood appear red. Other examples of chromoproteins include other hemochromes, , and flavoproteins.

In hemoglobin: chromoprotein (tetramer MW:4 x 16.125 =64.500) Heme: Fe++ four pyrrol rings.

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