Protoporphyrin IX
Encyclopedia
Protoporphyrin IX, in the metabolism of porphyrin
, is created by the enzyme protoporphyrinogen oxidase
.
converts it into heme b
(i.e. Fe-protoporphyrin IX or protoheme IX).
biosynthesis, the enzyme magnesium chelatase
converts it into Mg-protoporphyrin IX.
Porphyrin
Porphyrins are a group of organic compounds, many naturally occurring. One of the best-known porphyrins is heme, the pigment in red blood cells; heme is a cofactor of the protein hemoglobin. Porphyrins are heterocyclic macrocycles composed of four modified pyrrole subunits interconnected at...
, is created by the enzyme protoporphyrinogen oxidase
Protoporphyrinogen oxidase
Protoporphyrinogen oxidase is an enzyme that is responsible for the seventh step in heme production....
.
Heme b biosynthesis
In heme biosynthesis, the enzyme ferrochelataseFerrochelatase
Ferrochelatase is an enzyme that catalyses the terminal step in the biosynthesis of heme, converting protoporphyrin IX into heme. It catalyses the reaction:A ferrochelatase enzyme consists of 497 amino acid residues with a m.w...
converts it into heme b
Heme b
Heme B or haem B is the most abundant heme, both hemoglobin and myoglobin are examples of oxygen transport proteins that contain heme B. The peroxidase family of enzymes also contain heme B...
(i.e. Fe-protoporphyrin IX or protoheme IX).
Chlorophyll biosynthesis
In chlorophyllChlorophyll
Chlorophyll is a green pigment found in almost all plants, algae, and cyanobacteria. Its name is derived from the Greek words χλωρος, chloros and φύλλον, phyllon . Chlorophyll is an extremely important biomolecule, critical in photosynthesis, which allows plants to obtain energy from light...
biosynthesis, the enzyme magnesium chelatase
Magnesium chelatase
Magnesium-chelatase is a three-component enzyme that catalyses the insertion of Mg2+ into protoporphyrin IX. This is the first unique step in the synthesis of bacteriochlorophyll...
converts it into Mg-protoporphyrin IX.
See also
- Methyl aminolevulinateMethyl aminolevulinateMethyl aminolevulinate is a prodrug that is metabolised to Protoporphyrin IX used in photodynamic therapy. It is marketed as Metvix....
- Protoporphyrin for other roles of protoporphyrin IX