MMA is caused by a defect in the conversion of L-methylmalonyl-CoA to succinyl-CoA
, catalyzed by the enzyme methylmalonylCoA (MMCoA) mutase (EC.
Functional mut converts methylmalonic acid-CoA to succinyl-CoA
2] Malate dehydrogenase 4 NADH 10 Malate dehydrogenase -4 NADH -10 Malate dehydrogenase 4 NADH 10 Gluconeogenesis Phosphoenolpyruvate -4 carboxykinase Phosphoglycerate kinase -4 Glyceraldehyde 3-phosphate -4 NADH -10 dehydrogenase Glycolysis Glyceraldehyde 3-phosphate 4 NADH 10 dehydrogenase Phosphoglycerate kinase 4 Pyruvate kinase 4 Decarboxylation Pyruvate dehydrogenase 4 NADH 10 of Pyruvate complex Krebs cycle Isocitrate dehydrogenase 4 NADH 10 [alpha]-ketoglutarate 4 NADH 10 dehydrogenase complex Succinyl-CoA
synthetase 4 Succinate dehydrogenase 4 6 FAD[H.
Synthesis of methionine and succinyl-CoA
depends on the coenzyme activity of cobalamin.
The 3-hydroxypropianate cycle is another unidirectional pathway in which acetyl-CoA is reductively transformed through carboxylation reactions into succinyl-CoA
via the 3-hydroxypropianate intermediate.
These are further metabolized to yield acetyl-CoA, acetoacetate, and succinyl-CoA
and glycine through several steps requiring copper enzymes form d-aminolevulinic acid from which porphyrin is formed.
Succinate + FAD 8 ATP + Succinate + CoA Succinyl-CoA
C 8 [?
MMMconverts methylmalonyl-CoA to succinyl-CoA
, an intermediate in the Krebs cycle.
12]) dependent enzyme, which converts L-methylmalonyl-CoA to succinyl-CoA