Protein Domain : Methylmalonate-semialdehyde dehydrogenase IPR010061

Type	Family
Description	Methylmalonate-semialdehyde dehydrogenase (MMSDH, ) catalyses the irreversible NAD+- and CoA-dependent oxidative decarboxylation of methylmalonate semialdehyde to propionyl-CoA. Methylmalonate-semialdehyde dehydrogenase has been characterised in both prokaryotes [ , ] and eukaryotes [], functioning as a mammalian tetramer and a bacterial homodimer. Although similar in monomeric molecular mass and enzymatic activity, the N-terminal sequence in Pseudomonas aeruginosa does not correspond with the N-terminal sequence predicted for rat liver. Sequence homology to a variety of prokaryotic and eukaryotic aldehyde dehydrogenases places MMSDH in the aldehyde dehydrogenase (NAD+) superfamily making MMSDH's CoA requirement unique among known ALDHs. Methylmalonate semialdehyde dehydrogenase is closely related to betaine aldehyde dehydrogenase, 2-hydroxymuconic semialdehyde dehydrogenase, and class 1 and 2 aldehyde dehydrogenase []. In most cases these enzymes are involved in valine metabolism, but Gram-positive bacteria, such as Bacillus, contain a distinct subset. This subset of enzymes is encoded in an iol operon and is apparently involved in myo-inositol catabolism, converting malonic semialdehyde to acetyl CoA ad CO2 [ ].
Short Name	MeMal-semiAld_DH