Isopropylmalate dehydrogenase

Function

3-Isopropylmalate dehydrogenase (IMDH) catalyzes the oxidative decarboxylation of 3-isopropylmalate (3IPM) to 2-oxo-4-methylvalerate. This reaction is a step in the biosynthesis of leucine in bacteria and fungi. IMDH uses NAD as a cofactor. IMDH is a bifunctional enzyme that catalyzes dehydrogenation and decarboxylation in the presence of NAD and a divalent cation^[1].

Structural highlights

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IMDH active site containing the and contains the substrate and Mn+2 and K- ions^[2]. Water molecules shown as red spheres.

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