Methylmalonic aciduria type A protein, mitochondrial also known as MMAA is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the MMAA gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

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Function

The protein encoded by this gene is involved in the translocation of cobalamin

Cobamamide

Cobamamide , which is also known as adenosylcobalamin and dibencozide, is, along with methylcobalamin , one of the active forms of vitamin B12...

 into the mitochondrion

Mitochondrion

In cell biology, a mitochondrion is a membrane-enclosed organelle found in most eukaryotic cells. These organelles range from 0.5 to 1.0 micrometers in diameter...

, where it is used in the final steps of adenosylcobalamin synthesis. Adenosylcobalamin is a coenzyme required for the activity of methylmalonyl-CoA mutase

Methylmalonyl-CoA mutase

Methylmalonyl Coenzyme A mutase, also known as MCM is an enzyme that catalyzes the isomerization of methylmalonyl-CoA to succinyl-CoA and it is involved in key metabolic pathways...

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Clinical signficance

Mutations in the MMAA gene are associated with methylmalonic acidemia

Methylmalonic acidemia

Methylmalonic acidemia , also called methylmalonic aciduria, is an autosomal recessive metabolic disorder. It is a classical type of organic acidemia....

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External links

• GeneReviews/NCBI/NIH/UW entry on Methylmalonic Acidemia

Further reading