Sandbox Reserved 646
From Proteopedia
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= Arginase= | = Arginase= | ||
'''Arginase'''(PheOH), Arginase is an enzyme found within the important urea cycle. Arginase is the final enzyme that allows the Urea cycle to complete its fifth and last step. Arginase takes on two distinct forms: Class I and II. The grouping into classes refers to the catalytic activity that the enzyme is capable of performing. In addition, each class are encoded by a different gene. Arginase I (arg1) is found in the cytoplasm of liver cells functioning in the urea cycle, while arginase II (arg2) is found in the mitochondria and functions in the kidney. In interest of our studies, we will refer to arginase I as arginase. Arginase belongs to the enzymatic class hydrolase. Arginase functions by cleaving the amino acid arginine with water to produce urea. When one studies enzymes, he pays careful attention the it’s specific activity. Specific activity quantifies the amount of product formed by the enzyme in reference to a given time per concentration of a protein. Arginase is known to have high specific activity and functions to produce a good amount of urea.<ref>Corporation, Worthington Biochemical. Arginase [http://http://www.worthington-biochem.com/AR/default.html]</ref> In addition, this enzyme allows the regeneration of ornithine which is the final product of the urea cycle. When there is a deficiency in the arg1 gene it is understood that one is undergoing an urea cycle disorder. In people with arginase deficiency, arginase is either missing or harmed, therefore arginine is not metabolized correctly. In lieu of this, it is impossible for urea to be formed, leaving the excess nitrogen to accumulate in the blood in the form of ammonia. Which leads to serious problems in the body.<ref> Genetic Conditions - NIH Arginase Deficiency [http://ghr.nlm.nih.gov/condition/arginase-deficiency> | '''Arginase'''(PheOH), Arginase is an enzyme found within the important urea cycle. Arginase is the final enzyme that allows the Urea cycle to complete its fifth and last step. Arginase takes on two distinct forms: Class I and II. The grouping into classes refers to the catalytic activity that the enzyme is capable of performing. In addition, each class are encoded by a different gene. Arginase I (arg1) is found in the cytoplasm of liver cells functioning in the urea cycle, while arginase II (arg2) is found in the mitochondria and functions in the kidney. In interest of our studies, we will refer to arginase I as arginase. Arginase belongs to the enzymatic class hydrolase. Arginase functions by cleaving the amino acid arginine with water to produce urea. When one studies enzymes, he pays careful attention the it’s specific activity. Specific activity quantifies the amount of product formed by the enzyme in reference to a given time per concentration of a protein. Arginase is known to have high specific activity and functions to produce a good amount of urea.<ref>Corporation, Worthington Biochemical. Arginase [http://http://www.worthington-biochem.com/AR/default.html]</ref> In addition, this enzyme allows the regeneration of ornithine which is the final product of the urea cycle. When there is a deficiency in the arg1 gene it is understood that one is undergoing an urea cycle disorder. In people with arginase deficiency, arginase is either missing or harmed, therefore arginine is not metabolized correctly. In lieu of this, it is impossible for urea to be formed, leaving the excess nitrogen to accumulate in the blood in the form of ammonia. Which leads to serious problems in the body.<ref> Genetic Conditions - NIH Arginase Deficiency [http://ghr.nlm.nih.gov/condition/arginase-deficiency> | ||
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| + | == '''Mechanism''' == | ||
| + | NH4+ + α-ketoglutarate + NADPH + 2 H+ → glutamate + NADP+ + H2O | ||
| + | ::[Image:arginase.jpeg]] | ||
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| + | Glutamate dehydrogenase is important in nitrogen and glutamate metabolism and energy homeostasis. In the reaction above the forward reaction is essential in converting free ammonia and α-ketoglutarate to glutamate, an amino acid that is used for protein synthesis. The reverse reaction is key reaction that links amino acid metabolism with the Tricarboxylic Acid cycle (TCA cycle). Both reactions utilize nicotinamide nucleotide cofactors: NAD+ when nitrogen is released and NADPH when nitrogen is used. Glutamate dehydrogenase is regulated by cell energy charge. This requires Adenosine triphosphate (ATP) and Guanosine triphosphate (GTP) are positive allosteric effectors for the forward reaction and Adenosine diphosphate (ADP) and Guanosine diphosphate are positive allosteric effectors for the reverse reaction. When the level of ATP is high, conversion of glutamate to α-ketoglurate and other TCA cycle intermediates is limited; when the cellular energy charge is low, glutamate is converted to ammonia and oxidizable TCA cycle intermediates. Glutamate is an important amino acid since it gives an amine group for many transamination reactions, thus, glutamate dehydrogenase is essential in producing this amino acid. (9) | ||
Revision as of 00:25, 15 November 2012
| This Sandbox is Reserved from 30/08/2012, through 01/02/2013 for use in the course "Proteins and Molecular Mechanisms" taught by Robert B. Rose at the North Carolina State University, Raleigh, NC USA. This reservation includes Sandbox Reserved 636 through Sandbox Reserved 685. |
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More help: Help:Editing For more help, look at this link: http://proteopedia.org/w/Help:Getting_Started_in_Proteopedia ArginaseArginase(PheOH), Arginase is an enzyme found within the important urea cycle. Arginase is the final enzyme that allows the Urea cycle to complete its fifth and last step. Arginase takes on two distinct forms: Class I and II. The grouping into classes refers to the catalytic activity that the enzyme is capable of performing. In addition, each class are encoded by a different gene. Arginase I (arg1) is found in the cytoplasm of liver cells functioning in the urea cycle, while arginase II (arg2) is found in the mitochondria and functions in the kidney. In interest of our studies, we will refer to arginase I as arginase. Arginase belongs to the enzymatic class hydrolase. Arginase functions by cleaving the amino acid arginine with water to produce urea. When one studies enzymes, he pays careful attention the it’s specific activity. Specific activity quantifies the amount of product formed by the enzyme in reference to a given time per concentration of a protein. Arginase is known to have high specific activity and functions to produce a good amount of urea.[1] In addition, this enzyme allows the regeneration of ornithine which is the final product of the urea cycle. When there is a deficiency in the arg1 gene it is understood that one is undergoing an urea cycle disorder. In people with arginase deficiency, arginase is either missing or harmed, therefore arginine is not metabolized correctly. In lieu of this, it is impossible for urea to be formed, leaving the excess nitrogen to accumulate in the blood in the form of ammonia. Which leads to serious problems in the body.[2] |
