<p> A number of NAD-dependent 2-hydroxyacid dehydrogenases which seem to be specific for the D-isomer of their substrate have been shown to be functionally and structurally related. The catalytic domain contains a number of conserved charged residues which may play a role in the catalytic mechanism. The NAD-binding domain is described in <db_xref db="INTERPRO" dbkey="IPR006140"/> </p>