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
Famous quotes containing the words reactions of, reactions and/or metabolism:
“Cuteness in children is totally an adult perspective. The children themselves are unaware that the quality exists, let alone its desirability, until the reactions of grownups inform them.”
—Leontine Young (20th century)
“In this Journal, my pen is a delicate needle point, tracing out a graph of temperament so as to show its daily fluctuations: grave and gay, up and down, lamentation and revelry, self-love and self-disgust. You get here all my thoughts and opinions, always irresponsible and often contradictory or mutually exclusive, all my moods and vapours, all the varying reactions to environment of this jelly which is I.”
—W.N.P. Barbellion (1889–1919)
“He’s got a fifteen percent metabolism with an overactive thyroid and a glandular affectation of about three percent. With a one percent mentality. He’s what we designate as the Crummy Moronic type.”
—Robert Pirosh, U.S. screenwriter, George Seaton, George Oppenheimer, and Sam Wood. Dr. Hugo Z. Hackenbush (Groucho Marx)