|
Malic Enzyme
Malic enzyme may refer to '' decarboxylating'' malate dehydrogenases: * Malate dehydrogenase (decarboxylating) () or NAD-malic enzyme * Malate dehydrogenase (oxaloacetate-decarboxylating) (), another NAD-malic enzyme * Malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) Malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) () or NADP-malic enzyme (NADP-ME) is an enzyme that catalyzes the chemical reaction in the presence of a bivalent metal ion: :(S)-malate + NADP+ \rightleftharpoons pyruvate + CO2 + NADP ... () or NADP-malic enzyme including * D-malate dehydrogenase (decarboxylating) () {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decarboxylation
Decarboxylation is a chemical reaction that removes a carboxyl group and releases carbon dioxide (CO2). Usually, decarboxylation refers to a reaction of carboxylic acids, removing a carbon atom from a carbon chain. The reverse process, which is the first chemical step in photosynthesis, is called carboxylation, the addition of CO2 to a compound. Enzymes that catalyze decarboxylations are called decarboxylases or, the more formal term, carboxy-lyases ( EC number 4.1.1). In organic chemistry The term "decarboxylation" usually means replacement of a carboxyl group () with a hydrogen atom: :RCO2H -> RH + CO2 Decarboxylation is one of the oldest known organic reactions. It is one of the processes assumed to accompany pyrolysis and destructive distillation. Metal salts, especially copper compounds, facilitate the reaction via the intermediacy of metal carboxylate complexes. Decarboxylation of aryl carboxylates can generate the equivalent of the corresponding aryl anion, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydrogenase
A dehydrogenase is an enzyme belonging to the group of oxidoreductases that oxidizes a substrate by reducing an electron acceptor, usually NAD+/NADP+ or a flavin coenzyme such as FAD or FMN. Like all catalysts, they catalyze reverse as well as forward reactions, and in some cases this has physiological significance: for example, alcohol dehydrogenase catalyzes the oxidation of ethanol to acetaldehyde in animals, but in yeast it catalyzes the production of ethanol from acetaldehyde. IUBMB Classification Oxidoreductases, enzymes that catalyze oxidation-reduction reactions, constitute Class EC 1 of the IUBMB classification of enzyme-catalyzed reactions. Any of these may be called dehydrogenases, especially those in which NAD+ is the electron acceptor (oxidant), but reductase is also used when the physiological emphasis on reduction of the substrate, and oxidase is used ''only'' when O2 is the electron acceptor. The systematic name of an oxidoreductase is "donor:acceptor oxido ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malate Dehydrogenase (decarboxylating)
Malate dehydrogenase (decarboxylating) () or NAD-malic enzyme (NAD-ME) is an enzyme that catalyzes the chemical reaction :(S)-malate + NAD+ \rightleftharpoons pyruvate + CO2 + NADH Thus, the two substrates of this enzyme are (S)-malate and NAD+, whereas its three products are pyruvate, CO2, and NADH. Malate is oxidized to pyruvate and CO2, and NAD+ is reduced to NADH. This enzyme belongs to the family of oxidoreductases, to be specific, those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (S)-malate:NAD+ oxidoreductase (decarboxylating). This enzyme participates in pyruvate metabolism and carbon fixation. NAD-malic enzyme is one of three decarboxylation enzymes used in the inorganic carbon concentrating mechanisms of C4 and CAM plants. The others are NADP-malic enzyme and PEP carboxykinase Phosphoenolpyruvate carboxykinase (, PEPCK) is an enzyme in the lyase family used in the metabolic pathway of gluconeogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malate Dehydrogenase (oxaloacetate-decarboxylating)
In enzymology, a malate dehydrogenase (oxaloacetate-decarboxylating) () is an enzyme that catalyzes the chemical reaction below :(S)-malate + NAD+ \rightleftharpoons pyruvate + CO2 + NADH Thus, the two substrates of this enzyme are (S)-malate and NAD+, whereas its 3 products are pyruvate, CO2, and NADH. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (S)-malate:NAD+ oxidoreductase (oxaloacetate-decarboxylating). Other names in common use include malic enzyme, pyruvic-malic carboxylase, NAD+-specific malic enzyme, NAD+-malic enzyme, and NAD+-linked malic enzyme. This enzyme participates in pyruvate metabolism. Structural studies As of late 2007, 6 structures have been solved for this class of enzymes, with PDB accession codes , , , , , , , , , , , , and . See also * ME2 (gene) Malate dehydrogenase (oxaloacetate-decarboxylating), NAD-depend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malate Dehydrogenase (oxaloacetate-decarboxylating) (NADP+)
Malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) () or NADP-malic enzyme (NADP-ME) is an enzyme that catalyzes the chemical reaction in the presence of a bivalent metal ion: :(S)-malate + NADP+ \rightleftharpoons pyruvate + CO2 + NADPH Thus, the two substrates of this enzyme are (S)-malate and NADP+, whereas its 3 products are pyruvate, CO2, and NADPH. Malate is oxidized to pyruvate and CO2, and NADP+ is reduced to NADPH. This enzyme belongs to the family of oxidoreductases, to be specific those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (S)-malate:NADP+ oxidoreductase (oxaloacetate-decarboxylating). This enzyme participates in pyruvate metabolism and carbon fixation. NADP-malic enzyme is one of three decarboxylation enzymes used in the inorganic carbon concentrating mechanisms of C4 and CAM plants. The others are NAD-malic enzyme and PEP carboxykinase. Although often one of the three pho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
