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Urocanate Hydratase
Urocanase (also known as imidazolonepropionate hydrolase or urocanate hydratase) is the enzyme () that catalyzes the second step in the degradation of histidine, the hydration of urocanate into imidazolonepropionate. Urocanase is coded for by the UROC1 gene, located on the 3rd chromosome in humans. The protein itself is composed of 676 amino acids which then fold, producing the final product which has 2 identical subunits, making the enzyme a homodimer. To catalyze the hydrolysis of urocanate in the catabolic pathway of L-histidine the enzyme utilizes its two NAD+ (Nicotinamide Adnene Dinucleotide) groups. The NAD+ groups act as electrophiles, attaching to the top carbon of the urocanate which leads to sigmatropic rearrangement of the urocanate molecule. This rearrangement allows for the addition of a water molecule, converting the urocanate into 4,5-dihydro-4-oxo-5-imidazolepropanoate. : urocanate + H2O \rightleftharpoons 4,5-dihydro-4-oxo-5-imidazolepropanoate Inherited defi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imidazol-4-one-5-propionic Acid
Imidazol-4-one-5-propionic acid is an intermediate in the metabolism of histidine. It is a colorless compound that is sensitive to light in air. The compound features an imidazolone ring. Occurrence It arises via the action of urocanase on urocanic acid. Hydrolysis of the heterocycle to the glutamic acid derivative is catalyzed by imidazolonepropionate hydrolase. Microbial production of imidazol-4-one-5-propionic acid in the human gut has been shown to affect insulin signaling, which is relevant to type II diabetes. See also * Formiminoglutamic acid Formiminoglutamic acid (FIGLU; conjugate base, formiminoglutamate) is an intermediate in the catabolism of L-histidine to L-glutamic acid. It thus is also a biomarker for intracellular levels of folate. The FIGLU test is used to identify vitam ... * Urocanate * Urocanate hydratase References Carboxylic acids Imidazolines Lactams {{heterocyclic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urocanate
Urocanic acid is an intermediate in the catabolism of L-histidine. Metabolism 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 acid and subsequently to glutamic acid. Clinical significance Inherited deficiency of urocanase leads to elevated levels of urocanic acid in the urine, a condition known as urocanic aciduria. An important role for the onset of atopic dermatitis and asthma has been attributed to filaggrin, a skin precursor of urocanic acid. Urocanic acid is thought to be a significant attractant of the nematode parasite ''Strongyloides stercoralis'', in part because of relatively high levels in the plantar surfaces of the feet, the site through which this parasite often enters the body. Function Urocanic acid was detected in animal sweat and skin where, among other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imidazol-4-one-5-propionic Acid
Imidazol-4-one-5-propionic acid is an intermediate in the metabolism of histidine. It is a colorless compound that is sensitive to light in air. The compound features an imidazolone ring. Occurrence It arises via the action of urocanase on urocanic acid. Hydrolysis of the heterocycle to the glutamic acid derivative is catalyzed by imidazolonepropionate hydrolase. Microbial production of imidazol-4-one-5-propionic acid in the human gut has been shown to affect insulin signaling, which is relevant to type II diabetes. See also * Formiminoglutamic acid Formiminoglutamic acid (FIGLU; conjugate base, formiminoglutamate) is an intermediate in the catabolism of L-histidine to L-glutamic acid. It thus is also a biomarker for intracellular levels of folate. The FIGLU test is used to identify vitam ... * Urocanate * Urocanate hydratase References Carboxylic acids Imidazolines Lactams {{heterocyclic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urocanic Aciduria
Urocanic aciduria is an autosomal recessive metabolic disorder caused by a deficiency of the enzyme urocanase. It is a secondary disorder of histidine metabolism.''Disorders of histidine metabolism.''http://www.ommbid.com/OMMBID/the_online_metabolic_and_molecular_bases_of_inherited_disease/b/abstract/part8/ch80 Symptoms and signs Urocanic aciduria is thought to be relatively benign. Although aggressive behavior and mental retardation have been reported with the disorder, no definitive neurometabolic connection has yet been established. Genetics Urocanic aciduria has an autosomal recessive inheritance pattern, which means the defective gene is located on an autosome, and two copies of the gene – one copy inherited from each parent – are required in order to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but are usually not affected by the disorder. Pathophysiology The amino acid hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trifolium Repens
''Trifolium repens'', the white clover, is a herbaceous perennial plant in the bean family Fabaceae (otherwise known as Leguminosae). It is native to Europe, including the British Isles,Clapham, A.R., Tutin, T.G. and Warburg., E.F. 1968. ''Excursion Flora of the British Isles''. Cambridge University Press. and central Asia and is one of the most widely cultivated types of clover. It has been widely introduced worldwide as a forage crop, and is now also common in most grassy areas (lawns and gardens) of North America, Australia and New Zealand. The species includes varieties often classed as small, intermediate and large, according to height, which reflects petiole length. The term 'white clover' is applied to the species in general, 'Dutch clover' is often applied to intermediate varieties (but sometimes to smaller varieties), and 'ladino clover' is applied to large varieties. Name The genus name, ''Trifolium'', derives from the Latin ', "three", and ', "leaf", so called f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Families
A protein family is a group of evolutionarily related proteins. In many cases, a protein family has a corresponding gene family, in which each gene encodes a corresponding protein with a 1:1 relationship. The term "protein family" should not be confused with family as it is used in taxonomy. Proteins in a family descend from a common ancestor and typically have similar three-dimensional structures, functions, and significant sequence similarity. The most important of these is sequence similarity (usually amino-acid sequence), since it is the strictest indicator of homology and therefore the clearest indicator of common ancestry. A fairly well developed framework exists for evaluating the significance of similarity between a group of sequences using sequence alignment methods. Proteins that do not share a common ancestor are very unlikely to show statistically significant sequence similarity, making sequence alignment a powerful tool for identifying the members of protein familie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
