Reactions of Anaplerotic Metabolism
There are 4 major reactions classed as anaplerotic, yet the production of oxaloacetate from pyruvate has, it is estimated, the most physiologic importance.
| From | To | Reaction | Notes |
| Pyruvate | oxaloacetate | pyruvate + HCO3- + ATP oxaloacetate + ADP + Pi + H2O | This reaction is catalysed by pyruvate carboxylase, an enzyme activated by Acetyl-CoA, indicating a lack of oxaloacetate. It occurs in animal mitochondria.
Pyruvate can also be converted to L-malate, another intermediate, in a similar way. |
| Aspartate | oxaloacetate | - | This is a reversible reaction forming oxaloacetate from aspartate in a transamination reaction, via aspartate transaminase. |
| Glutamate | α-ketoglutarate | glutamate + NAD+ + H2O NH4+ + α-ketoglutarate + NADH + H+. | This reaction is catalysed by glutamate-dehydrogenase. |
| β-Oxidation of fatty acids | succinyl-CoA | - | When odd-chain fatty acids are oxidized, one molecule of succinyl-CoA is formed per fatty acid. The final enzyme is methylmalonyl-CoA mutase. |
The malate is created by PEP carboxylase and malate dehydrogenase in the cytosol. Malate, in the mitochondrial matrix, can be used to make pyruvate (catalyzed by malic enzyme) or oxaloacetic acid, both of which can enter the citric acid cycle.
Read more about this topic: Anaplerotic Reactions
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