You may also be interested in D-amino-acid oxidase (EC 1.4.3.3), a flavoprotein (FAD) highly specific for the D-form of amino acids, which was discovered by Hans Krebs in 1935 (see here), and which has a wide distribution (including in humans).
The enzyme has been very thoroughly investigated, in particular by Massey & co-workers (see here for example)
D-amino-acid oxidase (EC 1.4.3.3) catalyzes the reaction which results in the following transformation
D-amino acid + H2O + O2 = 2-oxo carboxylate + NH3 + H2O2
2-Oxo-carboxylates are what used to be called α-keto acids. For example, pyruvate is produced from D-Ala.
The product of the enzymatic reaction is the imino-acid which is nonenzymatically
hydrolyzed to a-keto acid (see Pollegioni et al., 1994, and references therein)
An excellent review
D-Amino Acid Oxidase: Physiological Role and Applications
by S. V. Khoronenkova & V. I. Tishkov,
Biochemistry (Moscow) is freely available from here
These authors have some intersting things to say about D-Serine, D-Proline and D-Alanine, and much more.
Additional Reference
- Pollegioni L, Fukui K, Massey V. (1994) Studies on the kinetic mechanism of pig kidney D-amino acid oxidase by site-directed mutagenesis of tyrosine 224 and tyrosine 228. J. Biol. Chem. 269, 31666-31673. [pdf]
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