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Adenosine Kinase
Adenosine kinase (AdK; EC 2.7.1.20) is an enzyme that catalyzes the transfer of gamma-phosphate from Adenosine triphosphate ( ATP) to adenosine (Ado) leading to formation of Adenosine monophosphate ( AMP). In addition to its well-studied role in controlling the cellular concentration of Ado, AdK also plays an important role in the maintenance of methylation reactions. All S-adenosylmethionine-dependent transmethylation reactions in cells lead to production of S-adenosylhomocysteine (SAH), which is cleaved by SAH hydrolase into Ado and homocysteine. The failure to efficiently remove these end products (Ado removed by phosphorylation by AdK) can result in buildup of SAH, which is a potent inhibitor of all transmethylation reactions. The disruption of AdK gene (-/-) in mice causes neonatal hepatic steatosis, a fatal condition characterized by rapid microvesicular fat infiltration, leading to early postnatal death. The liver was the main organ affected in these animals and in it the ... [...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] |
Adenosine Triphosphate
Adenosine triphosphate (ATP) is a nucleoside triphosphate that provides energy to drive and support many processes in living cell (biology), cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all known forms of life, it is often referred to as the "molecular unit of currency" for intracellular energy transfer. When consumed in a Metabolism, metabolic process, ATP converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. It is also a Precursor (chemistry), precursor to DNA and RNA, and is used as a coenzyme. An average adult human processes around 50 kilograms (about 100 mole (unit), moles) daily. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the Polyphosphate, triphosphate. Structure ATP consists of three parts: a sugar, an amine base ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine
Adenosine (symbol A) is an organic compound that occurs widely in nature in the form of diverse derivatives. The molecule consists of an adenine attached to a ribose via a β-N9- glycosidic bond. Adenosine is one of the four nucleoside building blocks of RNA (and its derivative deoxyadenosine is a building block of DNA), which are essential for all life on Earth. Its derivatives include the energy carriers adenosine mono-, di-, and triphosphate, also known as AMP/ADP/ATP. Cyclic adenosine monophosphate (cAMP) is pervasive in signal transduction. Adenosine is used as an intravenous medication for some cardiac arrhythmias. Adenosyl (abbreviated Ado or 5'-dAdo) is the chemical group formed by removal of the 5′-hydroxy (OH) group. It is found in adenosylcobalamin (an active form of vitamin B12) and as a radical in the radical SAM enzymes. Medical uses Supraventricular tachycardia In individuals with supraventricular tachycardia (SVT), adenosine is a first line trea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
S-Adenosyl Methionine
''S''-Adenosyl methionine (SAM), also known under the commercial names of SAMe, SAM-e, or AdoMet, is a common cosubstrate involved in methyl group transfers, transsulfuration, and aminopropylation. Although these anabolic reactions occur throughout the body, most SAM is produced and consumed in the liver. More than 40 methyl transfers from SAM are known, to various substrates such as nucleic acids, proteins, lipids and secondary metabolites. It is made from adenosine triphosphate (ATP) and methionine by methionine adenosyltransferase. SAM was first discovered by Giulio Cantoni in 1952. In bacteria, SAM is bound by the SAM riboswitch, which regulates genes involved in methionine or cysteine biosynthesis. In eukaryotic cells, SAM serves as a regulator of a variety of processes including DNA, tRNA, and rRNA methylation; immune response; amino acid metabolism; transsulfuration; and more. In plants, SAM is crucial to the biosynthesis of ethylene, an important plant hormone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homocysteine
Homocysteine (; symbol Hcy) is a non-proteinogenic α-amino acid. It is a homologous series, homologue of the amino acid cysteine, differing by an additional methylene bridge (). It is biosynthesized from methionine by the removal of its terminal Cε methyl group. In the body, homocysteine can be recycled into methionine or converted into cysteine with the aid of Vitamin B6, vitamin B6, Folate, B9, and Vitamin B12, B12. High levels of homocysteine in the blood (hyperhomocysteinemia) is regarded as a marker of cardiovascular disease, likely working through atherogenesis, which can result in Ischemia, ischemic injury. Therefore, hyperhomocysteinemia is a possible risk factor for coronary artery disease. Coronary artery disease occurs when an atherosclerotic plaque blocks blood flow to the Coronary artery, coronary arteries, which supply the heart with oxygenated blood. Hyperhomocysteinemia has been correlated with the occurrence of blood clots, heart attacks, and strokes, although ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypermethioninemia
Hypermethioninemia is an excess of the amino acid methionine, in the blood. This condition can occur when methionine is not broken down properly in the body. Presentation Genetics Hypermethioninemia can have different inheritance patterns. This condition is usually inherited in an autosomal recessive pattern, which means two copies of the gene in each cell are altered. Most often, the parents of an individual with an autosomal recessive disorder each carry one copy of the altered gene but do not show signs and symptoms of the disorder. Hypermethioninemia is occasionally inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In these cases, an affected person usually has one parent with the condition. Pathophysiology Inherited hypermethioninemia that is not associated with other metabolic disorders can be caused by shortages in the enzymes that break down methionine. These enzymes are produced from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encephalopathy
Encephalopathy (; ) means any disorder or disease of the brain, especially chronic degenerative conditions. In modern usage, encephalopathy does not refer to a single disease, but rather to a syndrome of overall brain dysfunction; this syndrome has many possible organic and inorganic causes. Types There are many types of encephalopathy. Some examples include: * Mitochondrial encephalopathy: Metabolic disorder caused by dysfunction of mitochondrial DNA. Can affect many body systems, particularly the brain and nervous system. * Acute necrotizing encephalopathy, rare disease that occurs following a viral infection. * Glycine encephalopathy: A genetic metabolic disorder involving excess production of glycine. * Hepatic encephalopathy: Arising from advanced cirrhosis of the liver. * Hypoxic ischemic encephalopathy: Permanent or transitory encephalopathy arising from severely reduced oxygen delivery to the brain. * Static encephalopathy: Unchanging, or permanent, brain damage, u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toyocamycin
Toyocamycin is a naturally occurring nucleoside antibiotic analog of adenosine. It was first isolated from the bacterium '' Streptomyces toyocaensis''. It has diverse biological activities including anticancer, antifungal, and antiviral properties. Besides ''S. toyocaensis'', it is found in '' Streptomyces sparsogenes'', '' Streptomyces diastatochromogenes'', '' Streptomyces rimosus'', and '' Tolypothrix tenuis''. Structure The chemical name of toyocamycin is 4-amino-7-(β-D-ribofuranosyl)-7''H''-pyrrolo ,3-''d''yrimidine-5-carbonitrile. It is an ''N''-glycosylpyrrolopyrimidine and a derivative of tubercidin, where the hydrogen at position 5 of the pyrrolopyrimidine ring is substituted with a nitrile group. Toyocamycin closely resembles adenosine, except that the nitrogen at position 7 of the purine ring is replaced by a carbon atom, and a nitrile group (-C≡N) is attached at that position. Structural similarity of toyocamycin with tubercidin and adenosine Biological acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubercidin
Tubercidin or 7-deaza-adenosine (7DA) is a naturally occurring nucleoside antibiotic and antimetabolite, chemically classified as an N-glycosylpyrrolopyrimidine. Structurally, it is a purine, purine analog of adenosine due to which it readily substitutes for adenosine in biological systems. This incorporation into DNA and RNA can disrupt nucleic acid metabolism, leading to cytotoxic effects. Tubercidin is produced by several microorganisms, including ''Streptomyces tubercidicus, Streptomyces tubericidicus'', ''Plectonema radiosum'', and ''Actinopolyspora erythraea''. It exhibits multiple biological activities, functioning as an antineoplastic agent, Antifungal, antibiotic antifungal agent, and Bacteria, bacterial metabolite. Because of its interference with Nucleic acid metabolism, nucleic acid synthesis, tubercidin shows promise for use in treating cancer and certain infections. Structure Tubercidin is systematically named (2R,3R,4S,5R)-2-(4-aminopyrrolo[2,3-d]pyrimidin-7-yl)-5-( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A-286501
A-286501 is an experimental drug that acts as a selective inhibitor of the enzyme adenosine kinase. In animal studies it has analgesic and antiinflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation, fever or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs reduce pain by inhibiting mechani ... effects. References Experimental drugs Diols Amines Bromoarenes Methyl compounds Pyrrolopyrimidines Cyclopentanols {{nervous-system-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
