Oxalosuccinic acid is a substrate of the
citric acid cycle. It is acted upon by
isocitrate dehydrogenase. Salts and
esters of oxalosuccinic acid are known as oxalosuccinates.
Oxalosuccinic acid/oxalosuccinate is an unstable 6-carbon intermediate in the
tricarboxylic acid cycle. It's a
keto acid, formed during the
oxidative decarboxylation
Oxidative decarboxylation is a decarboxylation reaction caused by oxidation. Most are accompanied by α- Ketoglutarate α- Decarboxylation caused by dehydrogenation of hydroxyl carboxylic acids such as carbonyl carboxylic acid, malic acid, isocitr ...
of
isocitrate
Isocitric acid is a structural isomer of citric acid. Since citric acid and isocitric acid are structural isomers, they share similar physical and chemical properties. Due to these similar properties, it is difficult to separate the isomers. Salt ...
to
alpha-ketoglutarate, which is catalyzed by the enzyme isocitrate dehydrogenase. Isocitrate is first oxidized by coenzyme
NAD+
Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an aden ...
to form oxalosuccinic acid/oxalosuccinate. Oxalosuccinic acid is both an alpha-keto and a beta-keto acid (an unstable compound) and it is the beta-ketoic property that allows the loss of carbon dioxide in the enzymatic reaction in conversion to the five-carbon molecule
2-oxoglutarate.
References
Tricarboxylic acids
Alpha-keto acids
Beta-keto acids
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