Protoporphyrin IX

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Protoporphyrin IX
Protoporphyrin IX.svg
553-12-8 YesY
3D model (Jmol) Interactive image
ChemSpider 10469486 N
ECHA InfoCard 100.008.213
PubChem 4971
Molar mass 562.658 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Protoporphyrin IX is an organic compound, which is one of the most common porphyrins in nature. It is a deeply colored pigment that is soluble in basic water. The free porphyrin is encountered in nature in the form of its iron complexes. When complexed with ferrous iron, the molecule is called heme. Hemes are prosthetic groups in some important proteins. These heme-containing proteins include hemoglobin, myoglobin, and cytochrome c. Complexes can also be formed with other metal ions, such as zinc.

Protoporphyrin IX biosynthesis[edit]

Its biosynthesis is mediated by the enzyme protoporphyrinogen oxidase. Protoporphyrin IX is an important precursor to biologically essential prosthetic groups such as heme, cytochrome c, and chlorophylls. As a result, a number of organisms are able to synthesize this tetrapyrrole from basic precursors such as glycine and succinyl CoA, or glutamate. Despite the wide range of organisms that synthesize protoporphyrin IX the process is largely conserved from bacteria to mammals with a few distinct exceptions in higher plants.[1][2][3]

Protoporphyrin IX Biosynthetic pathway

Heme b biosynthesis[edit]

In heme biosynthesis, the enzyme ferrochelatase converts it into heme b (i.e. Fe-protoporphyrin IX or protoheme IX).

Heme synthesis. Some reactions occur in the cytoplasm and some in the mitochondrion (yellow)

Chlorophyll biosynthesis[edit]

In chlorophyll biosynthesis, the enzyme magnesium chelatase converts it into Mg-protoporphyrin IX.

Synthesis of iron derivatives[edit]

Protoporphyrin IX reacts with iron salts in air to give the FeCl(PPIX).[4]

See also[edit]

  1. ^ A. R. Battersby; C. J. R. Fookes; G. W. J. Matcham; E. McDonald (1980). "Biosynthesis of the pigments of life: formation of the macrocycle". Nature. 285: 17–21. doi:10.1038/285017a0. 
  2. ^ F. J. Leeper (1983). "The biosynthesis of porphyrins, chlorophylls, and vitamin B12". Natural Product Reports. 2: 19–47. doi:10.1039/NP9850200019. 
  3. ^ G. Layer; J. Reichelt; D. Jahn (2010). "Structure and function of enzymes in heme biosynthesis". Protein Science. 19: 1137–1161. doi:10.1002/pro.405. 
  4. ^ Chang, C. K.; DiNello, R. K.; Dolphin, D. (1980). "Iron Porphines". Inorg. Synth. Inorganic Syntheses. 20: 147. doi:10.1002/9780470132517.ch35.