II. Definitions
- Porphyrin
- Porphyrins are cyclic molecule composed of four pyrrole rings connected by methine bridges
- Porphyrins have a central mineral (e.g. iron in heme, cobalt in Vitamin B12, Magnesium in chlorophyll)
- Porphyrins vary by their side chains and central mineral
- Porphyrins are formed from the single pyrrol ringed molecule, Porphobilinogen
- Protoporphyrins
- Protoporphyrins are Porphyrins that have four methyl, two vinyl, and two propionic acid side chains attached to their pyrrole rings
- Protoporphyrin 9
- Protoporphyrin 9 occurs in heme, which is a the prosthetic group in Hemoglobin, myoglobin, and most cytochromes
- Protopoprphyrin 9 is activated when Protoporphyrinogen's methylene bridge is cleaved by the enzyme Protoporphyrinogen oxidase
- Heme
- Heme is a Protoporphyrin 9 based prosthetic group, with a central ferrous 2+ ion (iron)
- Heme in combination with globin Protein, forms Hemoglobin
- Heme is also the the prosthetic group for myoglobin and most cytochromes (combined with different globin Proteins)
- Unlike Hemoglobin which contains 4 polypeptide chains, myoglobin contains only 1 polypeptide chain
- While heme in Hemoglobin transports oxygen, the heme in cytochromes transport electrons (Electron Transport Chain)
III. Physiology: Heme Metabolism
- Hemoglobin breakdown occurs when Red Blood Cells are destroyed (e.g. in Spleen at the end of their roughly 120 day life cycle)
- Hemoglobin is converted into Biliverdin and ultimately into Bilirubin for excretion
- See Bilirubin
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| Definition (NCI_CRCH) | A prosthetic group that consists of an iron atom contained in the center of a large heterocyclic organic ring called a porphyrin. |
| Definition (NCI_NCI-GLOSS) | The part of certain molecules that contains iron. The heme part of hemoglobin is the substance inside red blood cells that binds to oxygen in the lungs and carries it to the tissues. |
| Definition (MSH) | The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins. |
| Definition (CSP) | iron-porphyrin complex that is the color-furnishing portion of hemoglobin; found free in tissues and as the prosthetic group in many hemeproteins. |
| Concepts | Biologically Active Substance (T123) , Organic Chemical (T109) |
| MSH | D006418 |
| SnomedCT | 57813001 |
| English | Ferroprotoporphyrin, Heme, Heme b, Protoheme, Ferrate(2-), (7,12-diethenyl-3,8,13,17-tetramethyl-21H,23H-porphine-2,18-dipropanoato(4-)-N21,N22,N23,N24)-, dihydrogen, (SP-4-2)-, Haem, Protoheme IX, ferroheme, Heme [Chemical/Ingredient], haem, heme, Hemes, Reduced Hematin, Hematein, Benz(b)indeno(1,2-d)pyran-9(6h)-one, 6a,7-dihydro-3,4,6a,10-tetrahydroxy-, Hematin, Heme Group, HEME, HEMATEIN, Ferroheme, Haeme, Heme (substance), Reduced hematin, Hem |
| Swedish | Hem |
| Czech | hem |
| Finnish | Hemi |
| Italian | Protoeme IX, Eme b, Ferroprotoporfirina, Protoeme, Eme |
| Russian | GEM, FERROPROTOPORFIRIN, PROTOGEM, ГЕМ, ПРОТОГЕМ, ФЕРРОПРОТОПОРФИРИН |
| Spanish | Hemo, Protohemo, Hem (Hemoglobina), ferrohemo, ferroprotoporfirina, hematina reducida, hemo (sustancia), hemo, protohemo, Ferroprotoporfirina |
| French | Ferroprotoporphyrine, Ferrohème, Hème, Protohème |
| Polish | Żelazoporfiryna, Hem |
| Japanese | フェロプロトポルフィリン, ヘム, プロトヘム |
| German | Ferroprotoporphyrin, Häm, Protohäm |
| Portuguese | Ferroprotoporfirina, Heme, Protoheme |
Ontology: Porphyrins (C0032712)
| Definition (MSH) | A group of compounds containing the porphin structure, four pyrrole rings connected by methine bridges in a cyclic configuration to which a variety of side chains are attached. The nature of the side chain is indicated by a prefix, as uroporphyrin, hematoporphyrin, etc. The porphyrins, in combination with iron, form the heme component in biologically significant compounds such as hemoglobin and myoglobin. |
| Definition (CSP) | group of compounds containing the porphin structure, four pyrrole rings connected by methine bridges in a cyclic configuration to which a variety of side chains are attached; the nature of the side chain is indicated by a prefix, as uroporphyrin, hematoporphyrin, etc; the porphyrins, in combination with iron, form the heme component in biologically significant compounds such as hemoglobin and myoglobin. |
| Concepts | Biologically Active Substance (T123) , Organic Chemical (T109) |
| MSH | D011166 |
| SnomedCT | 15730005 |
| LNC | LP14913-5, MTHU002171 |
| English | Porphyrins, Porphyrins [Chemical/Ingredient], porphyrins, porphyrin, Porphyrin, Porphyrin (substance), Porphyrin, NOS |
| Swedish | Porfyriner |
| Czech | porfyriny |
| Finnish | Porfyriinit |
| Russian | PORFIRINY, ПОРФИРИНЫ |
| Croatian | PORFIRINI |
| Polish | Porfiryny |
| Spanish | porfirina (sustancia), porfirina, Porfirinas |
| French | Porphyrines |
| German | Porphyrine |
| Italian | Porfirine |
| Portuguese | Porfirinas |
Ontology: Protoporphyrins (C0033733)
| Definition (NCI) | A tetrapyrrole containing 4 methyl, 2 propionic and 2 vinyl side chains that is a metabolic precursor for hemes, cytochrome c and chlorophyll. Protoporphyrin IX is produced by oxidation of the methylene bridge of protoporphyrinogen by the enzyme protoporphyrinogen oxidase. |
| Definition (MSH) | Porphyrins with four methyl, two vinyl, and two propionic acid side chains attached to the pyrrole rings. Protoporphyrin IX occurs in hemoglobin, myoglobin, and most of the cytochromes. |
| Concepts | Biologically Active Substance (T123) , Organic Chemical (T109) |
| MSH | D011524 |
| SnomedCT | 51866008 |
| LNC | LP15839-1, MTHU004691 |
| English | Protoporphyrins, 3,7,12,17-Tetramethyl-8,13-divinyl-2,18-porphinedipropionic Acid, Protoporphyrins [Chemical/Ingredient], protoporphyrins, protoporphyrin, 3,3'-(3,7,12,17-Tetramethyl-8,13-divinylporphine-2,18-diyl)di(propionic acid), 7,12-diethenyl-3,8,13,17-tetramethylporphyrin-2,18-dipropanoic acid, PROTOPORPHYRIN, 2,18-Porphinedipropionic acid, 3,8,13,17-tetramethyl-7,12-divinyl- (8CI), PpIX, 3,7,12,17-tetramethyl-8,13-divinylporphyrin-2,18-dipropanoic acid, Protoporpyrin IX, Protoporphyrin IX, Ooporphyrin, 21H,23H-Porphine-2,18-dipropanoic acid, 7,12-diethenyl-3,8,13,17-tetramethyl-, 3,3'-(3,7,12,17-tetramethyl-8,13-divinyl-21H,23H-porphine-2,18-diyl)-bis-propionic acid, Protoporphyrin, Protoporphyrin (substance) |
| Swedish | Protoporfyriner |
| Czech | protoporfyriny |
| Finnish | Protoporfyriinit |
| Russian | PROTOPORFIRINY, ПРОТОПОРФИРИНЫ |
| French | Ooporphyrines, Protoporphyrines |
| Polish | Protoporfiryny |
| Spanish | protoporfirina (sustancia), protoporfirina, Protoporfirinas |
| German | Protoporphyrine |
| Italian | Protoporfirine |
| Portuguese | Protoporfirinas |
Ontology: protoporphyrin IX (C0072497)
| Concepts | Pharmacologic Substance (T121) |
| MSH | C028025 |
| SnomedCT | 80918003 |
| English | protoporphyrin IX, Protoporphyrin IX, Protoporphyrin IX (substance) |
| Spanish | protoporfirina IX (sustancia), protoporfirina IX |
