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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] |
Histidine
Histidine (symbol His or H) is an essential amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated –NH3+ form under biological conditions), a carboxylic acid group (which is in the deprotonated –COO− form under biological conditions), and an imidazole side chain (which is partially protonated), classifying it as a positively charged amino acid at physiological pH. Initially thought essential only for infants, it has now been shown in longer-term studies to be essential for adults also. It is encoded by the codons CAU and CAC. Histidine was first isolated by Albrecht Kossel and Sven Gustaf Hedin in 1896. It is also a precursor to histamine, a vital inflammatory agent in immune responses. The acyl radical is histidyl. Properties of the imidazole side chain The conjugate acid (protonated form) of the imidazole side chain in histidine has a p''K''a of approximately 6.0. Thus, below a pH of 6, the imidazole ring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imidazolone
Imidazolones are a family of heterocyclic compounds, the parents of which have the formula OC(NH)2(CH)2. Two isomers are possible, depending on the location of the carbonyl (CO) group. The NH groups are nonadjacent. A common route to imidazol-2-ones involves condensation of ureas and acyloins. Some are of interest in the pharmaceuticals.{{cite journal, journal=Chemistry of Heterocyclic Compounds, year=2015, volume=51, page=395–420 , title=Methods for the synthesis of 1-substituted 1H-imidazol-2(3H)-ones, first1=Maria M., last1=Antonova, first2=Vladimir V., last2=Baranov, first3=Angelina N., last3=Kravchenko, doi=10.1007/s10593-015-1716-3 4-Imidazolones arise from the condensation of amidines with 1,2-dicarbonyls such as glyoxal Glyoxal is an organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of .. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urocanase
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 defic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urocanic Acid
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 po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocycle
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different chemical element, elements as members of its ring(s). Heterocyclic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of these heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of known compounds are heterocycles. 59% of US FDA-approved drugs contain nitrogen heterocycles. Classification The study of heterocyclic chemistry focuses especially on unsaturated derivatives, and the preponderance of work and applications involves unstrained 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of pyridine, thiophene, pyrrole, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type II Diabetes
Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urination, and unexplained weight loss. Symptoms may also include increased hunger, feeling tired, and sores that do not heal. Often symptoms come on slowly. Long-term complications from high blood sugar include heart disease, strokes, diabetic retinopathy which can result in blindness, kidney failure, and poor blood flow in the limbs which may lead to amputations. The sudden onset of hyperosmolar hyperglycemic state may occur; however, ketoacidosis is uncommon. Type 2 diabetes primarily occurs as a result of obesity and lack of exercise. Some people are genetically more at risk than others. Type 2 diabetes makes up about 90% of cases of diabetes, with the other 10% due primarily to type 1 diabetes and gestational diabetes. In type 1 diabete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 vitamin B₁₂ deficiency, folate deficiency, and liver failure or liver disease. It is elevated with folate trapping, where it is accompanied by decreased methylmalonic acid, increased folate and a decrease in homocysteine. See also * Formiminotransferase cyclodeaminase * Glutamate-1-semialdehyde Glutamate-1-semialdehyde is a molecule formed from by the reduction of tRNA bound glutamate, catalyzed by glutamyl-tRNA reductase. It is isomerized by glutamate-1-semialdehyde 2,1-aminomutase to give aminolevulinic acid in the biosynthesis of ... * Glutamic acid * Imidazol-4-one-5-propionic acid References {{biochem-stub Dicarboxylic acids Amidines Amino acid derivatives ... [...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] |
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] |
Carboxylic Acids
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion. Examples and nomenclature Carboxylic acids are commonly identified by their trivial names. They at oftentimes have the suffix ''-ic acid''. IUPAC-recommended names also exist; in this system, carboxylic acids have an ''-oic acid'' suffix. For example, butyric acid (C3H7CO2H) is butanoic acid by IUPAC guidelines. For nomenclature of complex molecules containing a carboxylic acid, the carboxyl can be considered position one of the parent chain even if there are other substituents, such as 3-chloropropanoic acid. Alternately, it can be named as a "carboxy" or "carboxylic acid" substituent on another ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imidazolines
Imidazoline is a class of heterocycles formally derived from imidazoles by the reduction of one of the two double bonds. Three isomers are known, 2-imidazolines, 3-imidazolines, and 4-imidazolines. The 2- and 3-imidazolines contain an imine In organic chemistry, an imine ( or ) is a functional group or organic compound containing a carbon–nitrogen double bond (). The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bo ... center, whereas the 4-imidazolines contain an alkene group. The 2-Imidazoline group occurs in several drugs.Liu, H. and Du, D.-M. (2009), Recent Advances in the Synthesis of 2-Imidazolines and Their Applications in Homogeneous Catalysis. Adv. Synth. Catal., 351: 489–519. doi: 10.1002/adsc.200800797 References {{Organic-chemistry-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
