<P> Heme or haem is a coordination complex `` consisting of an iron ion coordinated to a porphyrin acting as a tetradentate ligand , and to one or two axial ligands . '' The definition is loose , and many depictions omit the axial ligands . Many porphyrin - containing metalloproteins have heme as their prosthetic group ; these are known as hemoproteins . Hemes are most commonly recognized as components of hemoglobin , the red pigment in blood , but are also found in a number of other biologically important hemoproteins such as myoglobin , cytochromes , catalases , heme peroxidase , and endothelial nitric oxide synthase . </P>
<P> Heme or haem is a coordination complex `` consisting of an iron ion coordinated to a porphyrin acting as a tetradentate ligand , and to one or two axial ligands . '' The definition is loose , and many depictions omit the axial ligands . Many porphyrin - containing metalloproteins have heme as their prosthetic group ; these are known as hemoproteins . Hemes are most commonly recognized as components of hemoglobin , the red pigment in blood , but are also found in a number of other biologically important hemoproteins such as myoglobin , cytochromes , catalases , heme peroxidase , and endothelial nitric oxide synthase . </P>
to what group of organic compounds does hemoglobin belong
to what group of organic compounds does hemoglobin belong
Heme or haem
Heme or haem