|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 18.104.22.1682
Enzymes and Genes:
|Haloferax mediterranei :||(D)-2-hydroxyacid dehydrogenase (NADP+)
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
(R)-2-hydroxybutanoate + NADP+ = 2-oxobutanoate + NADPH + H+ (22.214.171.1242)
Enzyme Commission Primary Name: D-2-hydroxyacid dehydrogenase (NADP+)
Enzyme Commission Synonyms: ddh (gene name)
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): 22.835754 [Latendresse13]
Enzyme Commission Summary:
This enzyme, characterized from the halophilic archaeon Haloferax mediterranei, catalyses a reversible stereospecific reduction of 2-ketocarboxylic acids into the corresponding D-2-hydroxycarboxylic acids. The enzyme prefers substrates with a main chain of 5 carbons (such as 4-methyl-2-oxopentanoate) to those with a shorter chain, and can use NADH with much lower efficiency. cf. EC 126.96.36.1995, (D)-2-hydroxyacid dehydrogenase (NAD+).
Instance reaction of [an (R)-2-hydroxycarboxylate + NADP+ = a 2-oxo carboxylate + NADPH + H+] (188.8.131.522):
i1: (R)-2-hydroxybutanoate + NADP+ = 2-oxobutanoate + NADPH + H+ (184.108.40.2062)
Domenech06: Domenech J, Ferrer J (2006). "A new D-2-hydroxyacid dehydrogenase with dual coenzyme-specificity from Haloferax mediterranei, sequence analysis and heterologous overexpression." Biochim Biophys Acta 1760(11);1667-74. PMID: 17049749
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