Heme Biosynthesis (Drosophila melanogaster)

From WikiPathways

Jump to: navigation, search
O2Fe2+hydroxymethylbilaneprotoporphyrin IXprotohemeuroporphyrinogen IIIBlack - reactantsRed - side productsporphobilinogen3 porphobilinogens + H2OO2coproporphyrinogen IIIrate limiting stepprotoporphyrinogen IX+HOMOLOGY MAPPPpoxdelta-aminolevulinatel(3)02640PbgsUpdoAlasCoAferrochelatasesuccinyl-CoACG1885ALAS1CoproxCO22 H2O4 NH3H2O4 CO22 CO2H2O22 H+glycinedelta-aminolevulinate


The enzymatic process that produces heme is properly called porphyrin synthesis, as all the intermediates are tetrapyrroles that are chemically classified are porphyrins. The process is highly conserved across biology. In humans, this pathway serves almost exclusively to form heme. In other species, it also produces similar substances such as cobalamin (vitamin B12).

The pathway is initiated by the synthesis of D-Aminolevulinic acid (dALA or ╬┤ALA) from the amino acid glycine and succinyl-CoA from the citric acid cycle (Krebs cycle). The rate-limiting enzyme responsible for this reaction, ALA synthase, is strictly regulated by intracellular iron levels and heme concentration. A low-iron level, e.g., in iron deficiency, leads to decreased porphyrin synthesis, which prevents accumulation of the toxic intermediates. This mechanism is of therapeutic importance: infusion of heme arginate or hematin can abort attacks of porphyria in patients with an inborn error of metabolism of this process, by reducing transcription of ALA synthase.

The organs mainly involved in heme synthesis are the liver and the bone marrow, although every cell requires heme to function properly. Heme is seen as an intermediate molecule in catabolism of haemoglobin in the process of bilirubin metabolism.

Source: Wikipedia http://en.wikipedia.org/wiki/Heme

Quality Tags

Ontology Terms



No bibliography


View all...
91030view07:02, 23 December 2016EgonwAdded missing metabolite IDs.
89928view13:35, 6 October 2016Mkutmonfixed xref
89922view13:34, 6 October 2016MkutmonModified description
71007view18:48, 22 September 2013EgonwConverted several labels to Metabolite DataNodes.
70237view21:25, 15 July 2013MaintBotupdated to 2013 schema
67335view10:39, 26 June 2013Christine ChichesterOntology Term : 'heme biosynthetic pathway' added !
40886view22:34, 1 March 2011MaintBotRemoved redundant pathway information and comments
35289view22:51, 11 February 2010Mills42Modified description
21245view11:31, 14 November 2008MaintBot[[Pathway:Drosophila melanogaster:Heme Biosynthesis]] moved to [[Pathway:WP269]]: Moved to stable identifier
8615view14:04, 7 January 2008MaintBotAdded to category $category
8613view14:04, 7 January 2008KdahlquistUploaded new pathway

External references


View all...
NameTypeDatabase referenceComment
2 CO2MetaboliteCHEBI:16526 (ChEBI)
2 H+Metabolite
2 H2OMetaboliteCHEBI:15377 (ChEBI)
4 CO2MetaboliteCHEBI:16526 (ChEBI)
4 NH3Metabolite
AlasGeneProduct37815 (Entrez Gene)
CG1885GeneProduct31817 (Entrez Gene)
CO2MetaboliteCHEBI:16526 (ChEBI)
CoAMetaboliteCHEBI:15346 (ChEBI)
CoproxGeneProduct44701 (Entrez Gene)
Fe2+MetaboliteCHEBI:29033 (ChEBI)
H2OMetaboliteCHEBI:15377 (ChEBI)
O2MetaboliteCHEBI:15379 (ChEBI)
PbgsGeneProduct39402 (Entrez Gene)
PpoxGeneProduct42939 (Entrez Gene)
UpdoGeneProduct35986 (Entrez Gene)
coproporphyrinogen IIIMetabolite
delta-aminolevulinateMetaboliteCHEBI:17549 (ChEBI)
ferrochelataseGeneProduct43757 (Entrez Gene)
glycineMetaboliteCHEBI:15428 (ChEBI)
l(3)02640GeneProduct46140 (Entrez Gene)
protoporphyrin IXMetabolite
protoporphyrinogen IXMetabolite
succinyl-CoAMetaboliteCHEBI:15380 (ChEBI)
uroporphyrinogen IIIMetabolite

Annotated Interactions

No annotated interactions

Personal tools