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Ureohydrolase
A ureohydrolase is a type of hydrolase enzyme. The ureohydrolase superfamily includes arginase (), agmatinase (), formiminoglutamase () and proclavaminate amidinohydrolase (). These enzymes share a 3-layer alpha-beta-alpha structure, and play important roles in arginine/agmatine metabolism, the urea cycle, histidine degradation, and other pathways. Arginase, which catalyses the conversion of arginine to urea and ornithine, is one of the five members of the urea cycle enzymes that convert ammonia to urea as the principal product of nitrogen excretion. There are several arginase isozymes that differ in catalytic, molecular and immunological properties. Deficiency in the liver isozyme leads to argininemia, which is usually associated with hyperammonemia. Agmatinase hydrolyses agmatine to putrescine, the precursor for the biosynthesis of higher polyamines, spermidine and spermine. In addition, agmatine may play an important regulatory role in mammals. Formiminoglutamase catalyses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agmatinase
In enzymology, an agmatinase () is an enzyme that catalyzes the chemical reaction :agmatine + H2O \rightleftharpoons putrescine + urea Thus, the two substrates of this enzyme are agmatine and H2O, whereas its two products are putrescine and urea. This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amidines. The systematic name of this enzyme class is agmatine amidinohydrolase. Other names in common use include agmatine ureohydrolase, and SpeB. This enzyme participates in urea cycle and metabolism of amino groups. Genetics In humans, the enzyme is encoded by the ''AGMAT'' gene. Structural studies As of late 2007, 5 structures A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as ... have been solved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arginase
Arginase (, ''arginine amidinase'', ''canavanase'', ''L-arginase'', ''arginine transamidinase'') is a manganese-containing enzyme. The reaction catalyzed by this enzyme is: : arginine + H2O → ornithine + urea It is the final enzyme of the urea cycle. It is ubiquitous to all domains of life. Structure and function Arginase belong to the ureohydrolase family of enzymes. Arginase catalyzes the fifth and final step in the urea cycle, a series of biochemical reactions in mammals during which the body disposes of harmful ammonia. Specifically, arginase converts L-arginine into L-ornithine and urea. Mammalian arginase is active as a trimer, but some bacterial arginases are hexameric. The enzyme requires a two-molecule metal cluster of manganese in order to maintain proper function. These Mn2+ ions coordinate with water, orienting and stabilizing the molecule and allowing water to act as a nucleophile and attack L-arginine, hydrolyzing it into ornithine and urea. In most mammals, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolase
Hydrolase is a class of enzyme that commonly perform as biochemical catalysts that use water to break a chemical bond, which typically results in dividing a larger molecule into smaller molecules. Some common examples of hydrolase enzymes are esterases including lipases, phosphatases, glycosidases, peptidases, and nucleosidases. Esterases cleave ester bonds in lipids and phosphatases cleave phosphate groups off molecules. An example of crucial esterase is acetylcholine esterase, which assists in transforming the neuron impulse into the acetate group after the hydrolase breaks the acetylcholine into choline and acetic acid. Acetic acid is an important metabolite in the body and a critical intermediate for other reactions such as glycolysis. Lipases hydrolyze glycerides. Glycosidases cleave sugar molecules off carbohydrates and peptidases hydrolyze peptide bonds. Nucleosidases hydrolyze the bonds of nucleotides. Hydrolase enzymes are important for the body because they have degra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L-glutamate
Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can synthesize enough for its use. It is also the most abundant excitatory neurotransmitter in the vertebrate nervous system. It serves as the precursor for the synthesis of the inhibitory gamma-aminobutyric acid (GABA) in GABA-ergic neurons. Its molecular formula is . Glutamic acid exists in three optically isomeric forms; the dextrorotatory -form is usually obtained by hydrolysis of gluten or from the waste waters of beet-sugar manufacture or by fermentation.Webster's Third New International Dictionary of the English Language Unabridged, Third Edition, 1971. Its molecular structure could be idealized as HOOC−CH()−()2−COOH, with two carboxyl groups −COOH and one amino group −. However, in the solid state and mildly acidic water solutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formamide
Formamide is an amide derived from formic acid. It is a colorless liquid which is miscible with water and has an ammonia-like odor. It is chemical feedstock for the manufacture of sulfa drugs and other pharmaceuticals, herbicides and pesticides, and in the manufacture of hydrocyanic acid. It has been used as a softener for paper and fiber. It is a solvent for many ionic compounds. It has also been used as a solvent for resins and plasticizers. Some astrobiologists suggest that it may be an alternative to water as the main solvent in other forms of life. Formamides are compounds of the type RR′NCHO. One important formamide is dimethylformamide, (CH3)2NCHO. Production Historical production In the past, formamide was produced by treating formic acid with ammonia, which produces ammonium formate, which in turn yields formamide upon heating: :HCOOH + NH3 → HCOO− :HCOO− → HCONH2 + H2O Formamide is also generated by aminolysis of ethyl formate: :HCOOCH2CH3 + NH3 → H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proclavaminate Amidinohydrolase
In enzymology, a proclavaminate amidinohydrolase () is an enzyme that catalyzes the chemical reaction :amidinoproclavaminate + H2O \rightleftharpoons proclavaminate + urea Thus, the two substrates of this enzyme are amidinoproclavaminate and H2O, whereas its two products are proclavaminate and urea. This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amidines. The systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ... of this enzyme class is amidinoproclavaminate amidinohydrolase. Other names in common use include PAH, and proclavaminate amidino hydrolase. This enzyme participates in clavulanic acid biosynthesis. References * * * * EC 3.5.3 Enzymes of unknown structu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
