| Primary Identifier | IPR043144 | Type | Homologous_superfamily |
| Short Name | Mal/L-sulf/L-lact_DH-like_ah |
| description | The malate dehydrogenase (MDH) of some extremophiles is more similar to the L-lactate dehydrogenases (L-LDH; ) from various sources than to other MDHs []. The archaebacterial MDH deviates from the eubacterial and eukaryotic enzymes having a low selectivity for the coenzyme (NAD(H) or NADP(H)) and catalysing the reduction of oxaloacetate to malate more efficiently than the reverse reaction []. It has been suggested that this class of dinucleotide cofactor-dependent dehydrogenases do not contain a Rossman-fold motif, as it was prior believed to be the case [].The enzyme is a dimer, where each subunit consists of three domains: domain I, domain II (NADPH binding domain), and domain III. Domain I contains N- and C-terminal regions and consists of the four-helix bundle []. The NADPH binding domain is formed of a seven-stranded antiparallel β-sheet fold [].This superfamily represents an α-helical domain found in bacterial and archaeal enzymes with malate, L-lactate, L-sulpholactate dehydrogenase activities, and related proteins. This domain has a four-helix barrel topology which forms an antiparallel pack, and is different from the typical four-helix bundle. |
