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Phosphoenolpyruvate Carboxykinase (ATP)
Phosphoenolpyruvate carboxykinase (ATP) (, ''phosphopyruvate carboxylase (ATP)'', ''phosphoenolpyruvate carboxylase'', ''phosphoenolpyruvate carboxykinase'', ''phosphopyruvate carboxykinase (adenosine triphosphate)'', ''PEP carboxylase'', ''PEP carboxykinase'', ''PEPCK (ATP)'', ''PEPK'', ''PEPCK'', ''phosphoenolpyruvic carboxylase'', ''phosphoenolpyruvic carboxykinase'', ''phosphoenolpyruvate carboxylase (ATP)'', ''phosphopyruvate carboxykinase'', ''ATP:oxaloacetate carboxy-lyase (transphosphorylating)'') is an enzyme with systematic name ''ATP:oxaloacetate carboxy-lyase (transphosphorylating; phosphoenolpyruvate-forming)''. This enzyme catalyses the following chemical reaction : ATP + oxaloacetate \rightleftharpoons ADP + phosphoenolpyruvate + CO2 See also * Phosphoenolpyruvate carboxykinase References External links * {{Portal bar, Biology, border=no EC 4.1.1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the 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 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 are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Enzymes
This article lists enzymes by their classification in the International Union of Biochemistry and Molecular Biology's Enzyme Commission (EC) numbering system. * List of EC numbers (EC 5) * List of EC numbers (EC 6) :Oxidoreductases (EC 1) (Oxidoreductase) *Dehydrogenase * Luciferase *DMSO reductase :EC 1.1 (act on the CH-OH group of donors) * :EC 1.1.1 (with NAD+ or NADP+ as acceptor) ** Alcohol dehydrogenase (NAD) ** Alcohol dehydrogenase (NADP) **Homoserine dehydrogenase ** Aminopropanol oxidoreductase **Diacetyl reductase **Glycerol dehydrogenase **Propanediol-phosphate dehydrogenase ** glycerol-3-phosphate dehydrogenase (NAD+) ** D-xylulose reductase **L-xylulose reductase **Lactate dehydrogenase **Malate dehydrogenase **Isocitrate dehydrogenase ** HMG-CoA reductase * :EC 1.1.2 (with a cytochrome as acceptor) * :EC 1.1.3 (with oxygen as acceptor) **Glucose oxidase **L-gulonolactone oxidase **Thiamine oxidase **Xanthine oxidase * :EC 1.1.4 (with a disul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalysis
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (chemistry), products, which usually have properties different from the reactants. Reactions often consist of a sequence o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxaloacetate
Oxaloacetic acid (also known as oxalacetic acid or OAA) is a crystalline organic compound with the chemical formula HO2CC(O)CH2CO2H. Oxaloacetic acid, in the form of its conjugate base oxaloacetate, is a metabolic intermediate in many processes that occur in animals. It takes part in gluconeogenesis, the urea cycle, the glyoxylate cycle, amino acid synthesis, fatty acid synthesis and the citric acid cycle. Properties Oxaloacetic acid undergoes successive deprotonations to give the dianion: :HO2CC(O)CH2CO2H −O2CC(O)CH2CO2H + H+, pKa = 2.22 :−O2CC(O)CH2CO2H −O2CC(O)CH2CO2− + H+, pKa = 3.89 At high pH, the enolizable proton is ionized: :−O2CC(O)CH2CO2− −O2CC(O−)CHCO2− + H+, pKa = 13.03 The enol forms of oxaloacetic acid are particularly stable, so much so that the two tautomers have different melting points (152 °C for the ''cis'' isoform and 184 °C for the ''trans'' isoform). This reaction is catalyzed by the enzyme oxaloacetate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphoenolpyruvate
Phosphoenolpyruvate (2-phosphoenolpyruvate, PEP) is the ester derived from the enol of pyruvate and phosphate. It exists as an anion. PEP is an important intermediate in biochemistry. It has the highest-energy phosphate bond found (−61.9 kJ/mol) in organisms, and is involved in glycolysis and gluconeogenesis. In plants, it is also involved in the biosynthesis of various aromatic compounds, and in carbon fixation; in bacteria, it is also used as the source of energy for the phosphotransferase system. In glycolysis PEP is formed by the action of the enzyme enolase on 2-phosphoglyceric acid. Metabolism of PEP to pyruvic acid by pyruvate kinase (PK) generates adenosine triphosphate (ATP) via substrate-level phosphorylation. ATP is one of the major currencies of chemical energy within cells. In gluconeogenesis PEP is formed from the decarboxylation of oxaloacetate and hydrolysis of one guanosine triphosphate molecule. This reaction is catalyzed by the enzyme pho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphoenolpyruvate Carboxykinase
Phosphoenolpyruvate carboxykinase (, PEPCK) is an enzyme in the lyase family used in the metabolic pathway of gluconeogenesis. It converts oxaloacetate into phosphoenolpyruvate and carbon dioxide. It is found in two forms, cytosolic and mitochondrial. Structure In humans there are two isoforms of PEPCK; a cytosolic form (SwissProt P35558) and a mitochondrial isoform (SwissProt Q16822) which have 63.4% sequence identity. The cytosolic form is important in gluconeogenesis. However, there is a known transport mechanism to move PEP from the mitochondria to the cytosol, using specific membrane transport proteins. PEP transport across the inner mitochondrial membrane involves the mitochondrial tricarboxylate transport protein and to a lesser extent the adenine nucleotide carrier. The possibility of a PEP/pyruvate transporter has also been put forward. X-ray structures of PEPCK provide insight into the structure and the mechanism of PEPCK enzymatic activity. The mitochondrial i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
