ENZYME

ENZYME entry: EC 1.1.99.31

Accepted Name

(S)-mandelate dehydrogenase.

Alternative Name(s)

L(+)-mandelate dehydrogenase.

MDH.

Reaction catalysed

(S)-2-hydroxy-2-phenylacetate + acceptor <=> 2-oxo-2-phenylacetate + reduced acceptor

Comment(s)

While all enzymes of this family oxidize the (S)-enantiomer of an alpha-hydroxy acid to an alpha-oxo acid, the ultimate oxidant (oxygen, intramolecular heme or some other acceptor) depends on the particular enzyme.
Transfers the electron pair from FMNH(2) to a component of the electron transport chain, most probably ubiquinone.
It is part of a metabolic pathway in Pseudomonads that allows these organisms to utilize mandelic acid, derivatized from the common soil metabolite amygdalin, as the sole source of carbon and energy.
Has a large active-site pocket and preferentially binds substrates with longer sidechains, e.g. 2-hydroxyoctanoate rather than 2-hydroxybutyrate.
It also prefers substrates that, like (S)-mandelate, have beta unsaturation, e.g. (indol-3-yl)glycolate compared with (indol-3- yl)lactate.
Esters of mandelate, such as methyl (S)-mandelate, are also substrates.

Cross-references

PROSITE

BRENDA

EC2PDB

ExplorEnz

PRIAM enzyme-specific profiles

KEGG Ligand Database for Enzyme Nomenclature