IUBMB Enzyme Nomenclature


Accepted name: D-2-hydroxyacid dehydrogenase (NAD+)

Reaction: an (R)-2-hydroxycarboxylate + NAD+ = a 2-oxocarboxylate + NADH + H+

Other name(s): LdhA; HdhD; D-2-hydroxyisocaproate dehydrogenase; R-HicDH; D-HicDH; (R)-2-hydroxy-4-methylpentanoate:NAD+ oxidoreductase; (R)-2-hydroxyisocaproate dehydrogenase; D-mandelate dehydrogenase (ambiguous)

Systematic name: (R)-2-hydroxycarboxylate:NAD+ oxidoreductase

Comments: 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, (D)-2-hydroxyacid dehydrogenase (NADP+).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Dengler, U., Niefind, K., Kiess, M. and Schomburg, D. Crystal structure of a ternary complex of D-2-hydroxyisocaproate dehydrogenase from Lactobacillus casei, NAD+ and 2-oxoisocaproate at 1.9 Å resolution. J. Mol. Biol. 267 (1997) 640-660. [PMID: 9126843]

2. Bonete, M.J., Ferrer, J., Pire, C., Penades, M. and Ruiz, J.L. 2-Hydroxyacid dehydrogenase from Haloferax mediterranei, a D-isomer-specific member of the 2-hydroxyacid dehydrogenase family. Biochimie 82 (2000) 1143-1150. [PMID: 11120357]

3. Kim, J., Darley, D., Selmer, T. and Buckel, W. Characterization of (R)-2-hydroxyisocaproate dehydrogenase and a family III coenzyme A transferase involved in reduction of L-leucine to isocaproate by Clostridium difficile. Appl. Environ. Microbiol. 72 (2006) 6062-6069. [PMID: 16957230]

4. Wada, Y., Iwai, S., Tamura, Y., Ando, T., Shinoda, T., Arai, K. and Taguchi, H. A new family of D-2-hydroxyacid dehydrogenases that comprises D-mandelate dehydrogenases and 2-ketopantoate reductases. Biosci. Biotechnol. Biochem. 72 (2008) 1087-1094. [PMID: 18391442]

5. Chambellon, E., Rijnen, L., Lorquet, F., Gitton, C., van Hylckama Vlieg, J.E., Wouters, J.A. and Yvon, M. The D-2-hydroxyacid dehydrogenase incorrectly annotated PanE is the sole reduction system for branched-chain 2-keto acids in Lactococcus lactis. J. Bacteriol. 191 (2009) 873-881. [PMID: 19047348]

6. Miyanaga, A., Fujisawa, S., Furukawa, N., Arai, K., Nakajima, M. and Taguchi, H. The crystal structure of D-mandelate dehydrogenase reveals its distinct substrate and coenzyme recognition mechanisms from those of 2-ketopantoate reductase. Biochem. Biophys. Res. Commun. 439 (2013) 109-114. [PMID: 23954635]

[EC created 2013]

Return to EC 1.1.1 home page
Return to EC 1.1 home page
Return to EC 1 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page