View source for DTDP-4-amino-4,6-dideoxygalactose transaminase

{{enzyme
| Name = histidinol-phosphate transaminase
| EC_number = 2.6.1.9
| CAS_number = 9032-98-8
| IUBMB_EC_number = 2/6/1/9
| GO_code = 0004400
| image = 
| width = 
| caption = 
}}
In [[enzymology]], a '''histidinol-phosphate transaminase''' ({{EC number|2.6.1.9}}) is an [[enzyme]] that [[catalysis|catalyzes]] the [[chemical reaction]]

:L-histidinol phosphate + 2-oxoglutarate <math>\rightleftharpoons</math> 3-(imidazol-4-yl)-2-oxopropyl phosphate + L-glutamate

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

This enzyme belongs to the family of [[transferase]]s, 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 [[metabolism|metabolic pathways]]: [[histidine metabolism]], [[tyrosine metabolism]], [[phenylalanine metabolism]], [[phenylalanine, tyrosine and tryptophan biosynthesis]], and [[novobiocin biosynthesis]].  It employs one [[cofactor (biochemistry)|cofactor]], [[pyridoxal phosphate]].

==Structural studies==

As of late 2007, 11 [[tertiary structure|structures]] have been solved for this class of enzymes, with [[Protein Data Bank|PDB]] accession codes {{PDB link|1FG3}}, {{PDB link|1FG7}}, {{PDB link|1GEW}}, {{PDB link|1GEX}}, {{PDB link|1GEY}}, {{PDB link|1H1C}}, {{PDB link|1IJI}}, {{PDB link|1UU0}}, {{PDB link|1UU1}}, {{PDB link|1UU2}}, and {{PDB link|2F8J}}.

==References==
{{reflist|1}}
* {{cite journal | author = AMES BN, HORECKER BL | year = 1956 | title = The biosynthesis of histidine:  imidazoleacetol phosphate transaminase | journal = J. Biol. Chem.  | volume = 220 | pages = 113&ndash;28  | pmid = 13319331 }}
* {{cite journal | author = Martin RG and Goldberger RF | year = 1963 | title = Imidazolylacetolphosphate:L-glutamate aminotransferase. Purification and properties | journal = J. Biol. Chem.  | volume = 242 | pages = 1168&ndash;1174 | pmid=5337155}}

[[Category:EC 2.6.1]]
[[Category:Pyridoxal phosphate enzymes]]
[[Category:Enzymes of known structure]]


{{transferase-stub}}