Which enzyme converts methylmalonyl-CoA to succinyl-CoA?

enzyme methylmalonyl-CoA mutase
The adenosylcobalamin-dependent enzyme methylmalonyl-CoA mutase catalyzes the conversion of methylmalonyl-CoA to succinyl-CoA in the degradation of propionate formed from odd-chain fatty acids (and an important energy source for ruminants, in which it is produced by rumen microflora).

What converts propionyl-CoA to Succinyl?

Major pathway of the conversion of propionyl-CoA into succinyl-CoA. The biotin-dependent enzyme propionyl-CoA carboxylase converts propionyl-CoA into D-methylmalonyl-CoA, which is then racemized into L-methylmalonyl-CoA and isomerized into succinyl-CoA, a Krebs cycle intermediate.

What does Methylmalonyl CoA Mutase do?

Methylmalonyl CoA mutase is responsible for a particular step in the breakdown of several protein building blocks (amino acids), specifically isoleucine, methionine, threonine, and valine. The enzyme also helps break down certain types of fats (lipids) and cholesterol.

What condition occurs when Methylmalonyl CoA Mutase is defective?

Methylmalonyl-Coenzyme A mutase deficiency (MCM deficiency) is a type of methylmalonic acidemia caused by having too little methylmalonyl-CoA mutase. Methylmalonyl-CoA mutase (MCM) is one of the special proteins (enzymes) needed to breakdown certain amino acids found in the food we eat.

What is the role of the coenzyme vitamin B12 in the reaction catalyzed by Methylmalonyl CoA Mutase?

In the mitochondria, vitamin B12 is required for the enzyme methylmalonyl CoA mutase, which converts methylmalonyl CoA to succinyl CoA, a step in odd-chain fatty acid oxidation and ketogenic amino acid catabolism.

Where does methylmalonyl-CoA come from?

The methylmalonyl-CoA unit that is the precursor to methyl-branched fatty acids and hydrocarbons arises from the carbon skeletons of valine and isoleucine, but not succinate (Dillwith et al., 1982).

Where does Methylmalonyl CoA come from?

What is the importance of Methylmalonyl CoA?

Methylmalonyl-CoA is the thioester consisting of coenzyme A linked to methylmalonic acid. It is an important intermediate in the biosynthesis of succinyl-CoA, which plays an essential role in the tricarboxylic acid cycle (aka the Citric Acid Cycle, or Krebs Cycle).

What is the importance of Methylmalonyl-CoA?

Where does Methylmalonyl-CoA come from?

How is succinyl-CoA formed?

Succinyl CoA can be formed from methylmalonyl CoA through the utilization of deoxyadenosyl-B12 (deoxyadenosylcobalamin) by the enzyme methylmalonyl-CoA mutase. This reaction, which requires vitamin B12 as a cofactor, is important in the catabolism of some branched-chain amino acids as well as odd-chain fatty acids.

What does succinyl-CoA do?

Succinyl-CoA synthetase (SCS) is the only mitochondrial enzyme capable of ATP production via substrate level phosphorylation in the absence of oxygen, but it also plays a key role in the citric acid cycle, ketone metabolism, and heme synthesis.

How can MMA levels be reduced?

A dose of 1,000 microg/day proved to be the most effective in lowering MMA levels to within normal limits. Serum tHcy was normalized in six of 11 subjects who had elevated tHcy pretreatment with oral Cbl alone and in one subject in combination with a multivitamin.

What enzyme converts succinyl-CoA to succinate?

Succinyl-CoA ligase, also called succinate synthase, is an enzyme in the Krebs cycle that converts succinyl-CoA to succinate and free coenzyme A, and converts ADP or guanosine diphosphate (GDP) to ATP or guanosine triphosphate (GTP) respectively (2,3).

How does succinyl-CoA synthetase work?

Succinyl-CoA synthetase (SCS) is the only mitochondrial enzyme capable of ATP production via substrate level phosphorylation in the absence of oxygen, but it also plays a key role in the citric acid cycle, ketone metabolism and heme synthesis.

How is Succinyl CoA generated?

What is the type of reaction undergone by the conversion of succinyl CoA into succinate?

Reaction 5: The conversion of succinyl-CoA to succinate This reaction is an example of a substrate level phosphorylation (page 228).

How does methylmalonyl CoA enter the tricarboxylic acid cycle?

methylmalonyl CoA undergoes an isomerization to succinyl CoA catalyzed by the B12-dependent enzyme methylmalonyl-CoA mutase and enters the tricarboxylic acid cycle (Figure 2). Yoshiharu Shimomura, Robert A. Harris, in Methods in Enzymology, 2000

What is methylmalonyl-CoA?

The methylmalonyl-CoA unit that is the precursor to methyl-branched fatty acids and hydrocarbons arises from the carbon skeletons of valine and isoleucine, but not succinate (Dillwith et al., 1982 ).

What is the role of methylmalonyl-CoA in gluconeogenesis?

Methylmalonyl-CoA is an inhibitor of pyruvate carboxylase, and its product, succinyl-CoA, is involved in gluconeogenesis by conversion to pyruvate (see earlier discussion).