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Adenosine Monophosphate
Adenosine monophosphate (AMP), also known as 5'-adenylic acid, is a nucleotide. AMP consists of a phosphate group, the sugar ribose, and the nucleobase adenine. It is an ester of phosphoric acid and the nucleoside adenosine. As a substituent it takes the form of the prefix adenylyl-. AMP plays an important role in many cellular metabolic processes, being interconverted to adenosine triphosphate (ATP) and adenosine diphosphate (ADP), as well as allosterically activating enzymes such as myophosphorylase-b. AMP is also a component in the synthesis of RNA. AMP is present in all known forms of life. Production and degradation AMP does not have the high energy phosphoanhydride bond associated with ADP and ATP. AMP can be produced from ADP by the myokinase (adenylate kinase) reaction when the ATP reservoir in the cell is low: : 2 ADP → ATP + AMP Or AMP may be produced by the hydrolysis of one high energy phosphate bond of ADP: : ADP + H2O → AMP + Pi AMP can also be forme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotide
Nucleotides are Organic compound, organic molecules composed of a nitrogenous base, a pentose sugar and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all Life, life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common Nutrient, nutrients by the liver. Nucleotides are composed of three subunit molecules: a nucleobase, a pentose, five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine, and thymine; in RNA, uracil is used in place of thymine. Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP), and uridine triph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Energy Phosphate
High-energy phosphate can mean one of two things: * The phosphate-phosphate (phosphoanhydride/phosphoric anhydride/macroergic/ phosphagen) bonds formed when compounds such as adenosine diphosphate (ADP) and adenosine triphosphate (ATP) are created. * The compounds that contain these bonds, which include the nucleoside diphosphates and nucleoside triphosphates, and the high-energy storage compounds of the muscle, the phosphagens. When people speak of a high-energy phosphate pool, they speak of the total concentration of these compounds with these high-energy bonds. __TOC__ Description High-energy phosphate bonds are usually pyrophosphate bonds, acid anhydride linkages formed by taking phosphoric acid derivatives and dehydrating them. As a consequence, the hydrolysis of these bonds is exergonic under physiological conditions, releasing Gibbs free energy. Except for PPi → 2 Pi, these reactions are, in general, not allowed to go uncontrolled in the human cell but are instead coupl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeostasis
In biology, homeostasis (British English, British also homoeostasis; ) is the state of steady internal physics, physical and chemistry, chemical conditions maintained by organism, living systems. This is the condition of optimal functioning for the organism and includes many variables, such as body temperature and fluid balance, being kept within certain pre-set limits (homeostatic range). Other variables include the pH of extracellular fluid, the concentrations of sodium, potassium, and calcium ions, as well as the blood sugar level, and these need to be regulated despite changes in the environment, diet, or level of activity. Each of these variables is controlled by one or more regulators or homeostatic mechanisms, which together maintain life. Homeostasis is brought about by a natural resistance to change when already in optimal conditions, and equilibrium is maintained by many regulatory mechanisms; it is thought to be the central motivation for all organic action. All home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AMP-activated Protein Kinase
5' AMP-activated protein kinase or AMPK or 5' adenosine monophosphate-activated protein kinase is an enzyme (EC 2.7.11.31) that plays a role in cellular energy homeostasis, largely to activate glucose and fatty acid uptake and oxidation when cellular energy is low. It belongs to a highly conserved eukaryotic protein family and its orthologues are SNF1 in yeast, and SnRK1 in plants. It consists of three proteins ( subunits) that together make a functional enzyme, conserved from yeast to humans. It is expressed in a number of tissues, including the liver, brain, and skeletal muscle. In response to binding AMP and ADP, the net effect of AMPK activation is stimulation of hepatic fatty acid oxidation, ketogenesis, stimulation of skeletal muscle fatty acid oxidation and glucose uptake, inhibition of cholesterol synthesis, lipogenesis, and triglyceride synthesis, inhibition of adipocyte lipogenesis, inhibition of adipocyte lipolysis, and modulation of insulin secretion by pancreat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uric Acid
Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the Chemical formula, formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown of purine nucleotides, and it is a normal component of urine. Hyperuricemia, High blood concentrations of uric acid can lead to gout and are associated with other medical conditions, including diabetes and the formation of ammonium acid urate kidney stones. Chemistry Uric acid was first isolated from kidney stones in 1776 by Swedish chemist Carl Wilhelm Scheele. In 1882, the Ukrainian chemist Ivan Horbaczewski first synthesized uric acid by melting urea with glycine. Uric acid displays lactam–lactim tautomerism. Uric acid crystallizes in the lactam form, with computational chemistry also indicating that tautomer to be the most stable. Uric acid is a diprotic acid with pKa, p''K''a1 = 5.4 and p''K''a2 =&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purine Nucleotide Cycle
The Purine Nucleotide Cycle is a metabolic pathway in protein metabolism requiring the amino acids aspartate and glutamate. The cycle is used to regulate the levels of adenine nucleotides, in which ammonia and fumarate are generated. AMP converts into IMP and the byproduct ammonia. IMP converts to S-AMP ( adenylosuccinate), which then converts to AMP and the byproduct fumarate. The fumarate goes on to produce ATP (energy) via oxidative phosphorylation as it enters the Krebs cycle and then the electron transport chain. Lowenstein first described this pathway and outlined its importance in processes including amino acid catabolism and regulation of flux through glycolysis and the Krebs cycle. AMP is produced after strenuous muscle contraction when the ATP reservoir is low (ADP > ATP) by the adenylate kinase (myokinase) reaction. AMP is also produced from adenine and adenosine directly; however, AMP can be produced through less direct metabolic pathways, such as de novo synth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catabolism
Catabolism () is the set of metabolic pathways that breaks down molecules into smaller units that are either oxidized to release energy or used in other anabolic reactions. Catabolism breaks down large molecules (such as polysaccharides, lipids, nucleic acids, and proteins) into smaller units (such as monosaccharides, fatty acids, nucleotides, and amino acids, respectively). Catabolism is the breaking-down aspect of metabolism, whereas anabolism is the building-up aspect. Cells use the monomers released from breaking down polymers to either construct new polymer molecules or degrade the monomers further to simple waste products, releasing energy. Cellular wastes include lactic acid, acetic acid, carbon dioxide, ammonia, and urea. The formation of these wastes is usually an oxidation process involving a release of chemical free energy, some of which is lost as heat, but the rest of which is used to drive the synthesis of adenosine triphosphate (ATP). This molecule acts as a way ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pungent smell. It is widely used in fertilizers, refrigerants, explosives, cleaning agents, and is a precursor for numeous chemicals. Biologically, it is a common nitrogenous waste, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers. Around 70% of ammonia produced industrially is used to make fertilisers in various forms and composition, such as urea and diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many chemicals. In many countries, it is classified as an List of extremely hazardous substances, extremely hazardous substance. Ammonia is toxic, cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myoadenylate Deaminase
AMP deaminase 1 is an enzyme that in humans is encoded by the ''AMPD1'' gene. Adenosine monophosphate deaminase is an enzyme that converts adenosine monophosphate (AMP) to inosine monophosphate (IMP), freeing an ammonia molecule in the process. Function Adenosine monophosphate deaminase 1 catalyzes the deamination of AMP to IMP in skeletal muscle and plays an important role in the purine nucleotide cycle. Two other genes have been identified, AMPD2 and AMPD3, for the liver- and erythrocyte-specific isoforms, respectively. Deficiency of the muscle-specific enzyme is apparently a common cause of exercise-induced myopathy and probably the most common cause of metabolic myopathy in the human. A research report shows that the widely prescribed diabetes medication metformin works on AMP-activated kinase (AMPK) by directly inhibiting AMP deaminase, thereby increasing cellular AMP. Regulation It has been shown that in environments with high potassium concentrations, AMP-deaminase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inosine Monophosphate
Inosinic acid or inosine monophosphate (IMP) is a nucleotide (that is, a nucleoside monophosphate). Widely used as a flavor enhancer, it is typically obtained from chicken byproducts or other meat industry waste. Inosinic acid is important in metabolism. It is the ribonucleotide of hypoxanthine and the first nucleotide formed during the synthesis of purine nucleotides. It can also be formed by the deamination of adenosine monophosphate by AMP deaminase. It can be hydrolysed to inosine. The enzyme deoxyribonucleoside triphosphate pyrophosphohydrolase, encoded by YJR069C in ''Saccharomyces cerevisiae'' and containing (d)ITPase and (d)XTPase activities, hydrolyzes inosine triphosphate (ITP) releasing pyrophosphate and IMP. Important derivatives of inosinic acid include the purine nucleotides found in nucleic acids and adenosine triphosphate, which is used to store chemical energy in muscle and other tissues. In the food industry, inosinic acid and its salts such as disodium in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidative Phosphorylation
Oxidative phosphorylation(UK , US : or electron transport-linked phosphorylation or terminal oxidation, is the metabolic pathway in which Cell (biology), cells use enzymes to Redox, oxidize nutrients, thereby releasing chemical energy in order to produce adenosine triphosphate (ATP). In eukaryotes, this takes place inside mitochondria. Almost all aerobic organisms carry out oxidative phosphorylation. This pathway is so pervasive because it releases more energy than alternative fermentation (biochemistry), fermentation processes such as anaerobic glycolysis. The energy stored in the chemical bonds of glucose is released by the cell in the citric acid cycle, producing carbon dioxide and the energetic reducing agent, electron donors NADH and FADH. Oxidative phosphorylation uses these molecules and O2 to ATP synthase, produce ATP, which is used throughout the cell whenever energy is needed. During oxidative phosphorylation, electrons are transferred from the electron donors to a ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
