- Urocanic acid
Section1= Chembox Identifiers
Section2= Chembox Properties
Section3= Chembox Hazards
Urocanic acid is an intermediate in the
catabolismof L- histidine.
It is formed from L-histidine through the action of
histidine ammonialyase(also known as histidase or histidinase) by elimination of ammonium.
In the liver, urocanic acid is transformed by
urocanate hydratase(or urocanase) to 4-imidazolone-5-propionic acidand subsequently to glutamic acid.
Inherited deficiency of urocanase leads to elevated levels of urocanic acid in the urine, a condition known as
Urocanic acid was detected in animal sweat and skin where, among other possible functions, it acts as an endogenous sunscreen or photoprotectant against
UVB-induced DNA damage. Urocanic acid is found predominantly in the stratum corneumof the skin and it is likely that most of it is derived from filaggrincatabolism (a histidine-rich protein). When exposed to UVB irradiation, trans-urocanic acid is converted "in vitro" and "in vivo" to the cis isomer. The cis form is known to activate suppressor T cells.
Urocanic acid was first isolated in 1874 by the chemist M. Jaffé from the urine of a dog, [Jaffé, M. (1874) Concerning a new constituent in the urine of dogs. "Ber. Deut. Chem. Ges." 7, 1669-1673.] hence the name (
Latin: "urina" = urine, and "canis" = dog).
Inborn error of metabolism
* [http://books.mcgraw-hill.com/getommbid.php?isbn=0071459960&template=ommbid&c=80 The Online Metabolic and Molecular Bases of Inherited Disease - Chapter 80] - An overview of disorders of histidine metabolism, including urocanic aciduria.
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См. также в других словарях:
urocanic acid — 4 Imidazoleacrylic acid; an acid derived from the oxidative deamination of l histidine; present in sweat and in dog s urine; elevated levels are observed in cases of urocanate hydratase deficiency. The cis form, resulting from exposure to UV… … Medical dictionary
urocanic acid — noun An intermediate in the catabolism of L histidine, transformed in the liver by urocanate hydratase (or urocanase) into 4 imidazolone 5 propionic acid and subsequently to glutamic acid … Wiktionary
urocanic acid — |yu̇rə|kanik , kānik noun Etymology: ur (I) + canine + ic : a crystalline acid C3H3N2CH . CHCOOH obtained first from the urine of a dog and formed by the enzymic deamination of histidine; 4(or 5) imidazole acrylic acid … Useful english dictionary
urocanic acid — noun Etymology: 1ur + canine + ic; from its being first obtained from the urine of a dog Date: circa 1903 a crystalline acid C6H6N2O2 that is normally present in human skin … New Collegiate Dictionary
urocanic acid — Intermediate in degradation of L histidine … Dictionary of molecular biology
Urocanic aciduria — Infobox Disease Name = PAGENAME Caption = Urocanic acid DiseasesDB = 32605 ICD10 = ICD10|E|70|8|e|70 ICD9 = ICD9|270.5 ICDO = OMIM = 276880 MedlinePlus = eMedicineSubj = eMedicineTopic = MeshID = D014560 Urocanic aciduria, also called urocanate… … Wikipedia
urocanic aciduria — Elevated levels of urocanic acid in the urine … Medical dictionary
Glutamic acid — Glutamic acid … Wikipedia
Oxaloacetic acid — Oxaloacetic acid … Wikipedia
Homogentisic acid — IUPAC name (2,5 Dihydroxyphenyl)acetic acid … Wikipedia