malic enzyme การใช้

• The others are NAD-malic enzyme and PEP carboxykinase.
• The ME3 gene stands for mitochondrial malic enzyme 3 precursor.
• Malic enzyme catalyzes the oxidative decarboxylation of malate to pyruvate using either NAD + or NADP + as a cofactor.
• The malate is created by malic enzyme ) or oxaloacetic acid, both of which can enter the citric acid cycle.
• The key enzymes in these processes are : NADP-linked malic enzyme, NADP-linked isocitrate dehydrogenase, NADP-linked glutamate dehydrogenase and nicotinamide nucleotide transhydrogenase.
• Mammalian tissues contain 3 distinct isoforms of malic enzyme : a cytosolic NADP ( + )-dependent isoform, a mitochondrial NADP ( + )-dependent isoform, and a mitochondrial NAD ( + )-dependent isoform.
• In a broader context, malic enzymes are found within a wide range of eukaryotic organisms, from fungi to mammals, and beyond that, are shown to localize in range of subcellular locations, including the cytosol, mitochondria, and chloroplast.
• There, depending on plant species, it is cleaved into pyruvate and either by malic enzyme or by PEP carboxykinase . is then introduced into the Calvin cycle, a coupled and self-recovering enzyme system, which is used to build branched carbohydrates.
• NADP-malic enzyme, as all other C 4 decarboxylases, did not evolve de novo for CO 2 pooling to aid RuBisCO . Rather, NADP-ME was directly transformed from a C 3 species in photosynthesis, and even earlier origins from an ancient cystolic ancestor.
• This cycle is usually studied in relation to Glucose Stimulated Insulin Secretion ( or GSIS ) and there is thought to be a relationship between the insulin response and NADPH produced from this cycle but the specifics are not clear and particular confusion exists about the role of malic enzymes.
• Figure legend : blue color = reaction steps of the citric acid cycle; brown color = reaction steps of the malate aspartate shuttle; green color = enzymes overexpressed in tumors . 1 = glutaminase, 2 = GOT, 3 = ?-ketoglutarate dehydrogenase, 4 = succinate dehydrogenase, 5 = fumarase, 6 = malate dehydrogenase, 7a = cytosolic malic enzyme, 7b = mitochondrial malic enzyme, 8 = citrate synthase, 9 = aconitase, 10 = lactate dehydrogenase
• Figure legend : blue color = reaction steps of the citric acid cycle; brown color = reaction steps of the malate aspartate shuttle; green color = enzymes overexpressed in tumors . 1 = glutaminase, 2 = GOT, 3 = ?-ketoglutarate dehydrogenase, 4 = succinate dehydrogenase, 5 = fumarase, 6 = malate dehydrogenase, 7a = cytosolic malic enzyme, 7b = mitochondrial malic enzyme, 8 = citrate synthase, 9 = aconitase, 10 = lactate dehydrogenase