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histidinol-phosphate transaminase
Histidinol-phosphate transaminase homodimer, E.Coli
Identifiers
EC no. 2.6.1.9
CAS no. 9032-98-8
Databases
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / QuickGO
Search
PMC articles
PubMed articles
NCBI proteins

In enzymology, a histidinol-phosphate transaminase ( EC 2.6.1.9) is an enzyme that catalyzes the chemical reaction

L-histidinol phosphate + 2-oxoglutarate 3-(imidazol-4-yl)-2-oxopropyl phosphate + L-glutamate

Thus, the two substrates of this enzyme are L-histidinol phosphate and 2-oxoglutarate, whereas its two products are 3-(imidazol-4-yl)-2-oxopropyl phosphate and L-glutamate.

This enzyme belongs to the family of transferases, specifically the transaminases, which transfer nitrogenous groups. The systematic name of this enzyme class is L-histidinol-phosphate:2-oxoglutarate aminotransferase. Other names in common use include imidazolylacetolphosphate transaminase, glutamic-imidazoleacetol phosphate transaminase, histidinol phosphate aminotransferase, imidazoleacetol phosphate transaminase, L-histidinol phosphate aminotransferase, histidine:imidazoleacetol phosphate transaminase, IAP transaminase, and imidazolylacetolphosphate aminotransferase. This enzyme participates in 5 metabolic pathways: histidine metabolism, tyrosine metabolism, phenylalanine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and novobiocin biosynthesis. It employs one cofactor, pyridoxal phosphate.

Structural studies

As of late 2007, 11 structures have been solved for this class of enzymes, with PDB accession codes 1FG3, 1FG7, 1GEW, 1GEX, 1GEY, 1H1C, 1IJI, 1UU0, 1UU1, 1UU2, and 2F8J.

References

  • AMES BN, HORECKER BL (1956). "The biosynthesis of histidine: imidazoleacetol phosphate transaminase". J. Biol. Chem. 220 (1): 113–28. PMID  13319331.
  • Martin RG; Goldberger RF (1963). "Imidazolylacetolphosphate:L-glutamate aminotransferase. Purification and properties". J. Biol. Chem. 242 (6): 1168–1174. PMID  5337155.