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IUPAC name
S-[2-[3-[[4-[[[(2R,3S,4R,5R)-5-(6-aminopurin-9-yl)-4-hydroxy-3-phosphonooxyoxolan-2-yl]methoxy-hydroxyphosphoryl]oxy-hydroxyphosphoryl]oxy-2-hydroxy-3,3-dimethylbutanoyl]amino]propanoylamino]ethyl] propanethioate
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Other names
Propionyl Coenzyme A; Propanoyl Coenzyme A
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Identifiers | |
3D model (JSmol)
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ChemSpider | |
ECHA InfoCard | 100.005.698 |
MeSH | propionyl-coenzyme+A |
PubChem CID
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Properties | |
C24H40N7O17P3S | |
Molar mass | 823.60 g/mol |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|
Infobox references | |
Propionyl-CoA is a coenzyme A derivative of propionic acid.
There are several different ways in which it is formed:
In mammals, propionyl-CoA is converted to (S)-methylmalonyl-CoA by propionyl-CoA carboxylase, a biotin-dependent enzyme also requiring bicarbonate and ATP.
This product is converted to (R)-methylmalonyl-CoA by methylmalonyl-CoA racemase.
(R)-Methylmalonyl-CoA is converted to succinyl-CoA, an intermediate in the tricarboxylic acid cycle, by methylmalonyl-CoA mutase, an enzyme requiring cobalamin to catalyze the carbon-carbon bond migration.
The methylmalonyl-CoA mutase mechanism begins with the cleavage of the bond between the 5' CH
2- of 5'-deoxyadenosyl and the cobalt, which is in its 3+ oxidation state (III), which produces a 5'-deoxyadenosyl radical and cobalamin in the reduced Co(II) oxidation state.
Next, this radical abstracts a hydrogen atom from the methyl group of methylmalonyl-CoA, which generates a methylmalonyl-CoA radical. It is believed that this radical forms a carbon-cobalt bond to the coenzyme, which is then followed by the rearrangement of the substrate's carbon skeleton, thus producing a succinyl-CoA radical. This radical then goes on to abstract a hydrogen from the previously produced 5'-deoxyadenosine, again creating a deoxyadenosyl radical, which attacks the coenzyme to reform the initial complex.
A defect in methylmalonyl-CoA mutase enzyme results in methylmalonic aciduria, a dangerous disorder that causes a lowering of blood pH.
In plants and insects propionyl-CoA is metabolized to acetate in a very different way, similar to beta-oxidation.