The enzymes, characterized from bacteria (Peptoclostridium difficile, Enterococcus faecalis and from lactic acid bacteria) prefer substrates with a main chain of 5 carbons (such as 4-methyl-2-oxopentanoate) to those with a shorter chain. It also utilizes phenylpyruvate. The enzyme from the halophilic archaeon Haloferax mediterranei prefers substrates with a main chain of 3-4 carbons (pyruvate and 2-oxobutanoate). cf. EC 1.1.1.272, (D)-2-hydroxyacid dehydrogenase (NADP+).
Crystal structure of a ternary complex of D-2-hydroxyisocaproate dehydrogenase from Lactobacillus casei, NAD+ and 2-oxoisocaproate at 1.9 A resolution.
Characterization of (R)-2-hydroxyisocaproate dehydrogenase and a family III coenzyme A transferase involved in reduction of L-leucine to isocaproate by Clostridium difficile.
Miyanaga A, Fujisawa S, Furukawa N, Arai K, Nakajima M, Taguchi H
Title
The crystal structure of D-mandelate dehydrogenase reveals its distinct substrate and coenzyme recognition mechanisms from those of 2-ketopantoate reductase.