oxaloacetate
Quick Summary
Oxaloacetate is a salt or ester of oxaloacetic acid. It is a four-carbon compound that plays a crucial role in the tricarboxylic acid cycle (TCA cycle), a key stage of cellular respiration.12
In the TCA cycle, acetyl CoA reacts with oxaloacetate to initiate the cycle, ultimately leading to the regeneration of oxaloacetate. This regeneration is essential for the continuous breakdown of fuel molecules like glucose, fatty acids, and amino acids to harvest energy for the cell. Oxaloacetate is also involved in anaplerotic reactions, which replenish TCA cycle intermediates when they are removed for biosynthesis. It can be formed from pyruvate or phosphoenolpyruvate through reactions that fix carbon dioxide.234
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metabolismIncomplete oxidation…coenzyme A; the four-carbon compound oxaloacetate; and the five-carbon compound α-oxoglutarate. The first, acetate in the form of acetyl coenzyme A, constitutes by far the most common product—it is the product of two-thirds of the carbon incorporated into carbohydrates and glycerol; all of the carbon in most fatty acids; and…
Read More…coenzyme A; the four-carbon compound oxaloacetate; and the five-carbon compound α-oxoglutarate. The first, acetate in the form of acetyl coenzyme A, constitutes by far the most common product—it is the product of two-thirds of the carbon incorporated into carbohydrates and glycerol; all of the carbon in most fatty acids; and…
Read More- metabolismFormation of coenzyme A, carbon dioxide, and reducing equivalent
…coenzyme A initially reacts with oxaloacetate to yield citrate and to liberate coenzyme A. This reaction [38] is catalyzed by citrate synthase. (As mentioned above, many of the compounds in living cells that take part in metabolic pathways exist as charged moieties, or anions, and are named as such.) Citrate…
Read More…coenzyme A initially reacts with oxaloacetate to yield citrate and to liberate coenzyme A. This reaction [38] is catalyzed by citrate synthase. (As mentioned above, many of the compounds in living cells that take part in metabolic pathways exist as charged moieties, or anions, and are named as such.) Citrate…
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photosynthesisCarbon fixation in C4 plants…reaction is the four-carbon acid oxaloacetate, which is reduced to malate, another four-carbon acid, in one form of the C4 pathway. Malate then is transported to bundle-sheath cells, which are located near the vascular system of the leaf. There, malate enters the chloroplasts and is oxidized and decarboxylated (i.e., loses…
Read More…reaction is the four-carbon acid oxaloacetate, which is reduced to malate, another four-carbon acid, in one form of the C4 pathway. Malate then is transported to bundle-sheath cells, which are located near the vascular system of the leaf. There, malate enters the chloroplasts and is oxidized and decarboxylated (i.e., loses…
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plantSpecific variations in photosynthesis…product is the four-carbon acid oxaloacetate—hence the designation C4 plants. Oxaloacetate is reduced to malate, which is transferred to a thick-walled bundle sheath cell. Malate is decarboxylated, giving rise to high CO2 concentrations in the bundle sheath. Here, Rubisco of the Calvin-Benson cycle functions more efficiently because oxygenation is suppressed.…
Read More…product is the four-carbon acid oxaloacetate—hence the designation C4 plants. Oxaloacetate is reduced to malate, which is transferred to a thick-walled bundle sheath cell. Malate is decarboxylated, giving rise to high CO2 concentrations in the bundle sheath. Here, Rubisco of the Calvin-Benson cycle functions more efficiently because oxygenation is suppressed.…
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