Requires Mn2+ or Mg2+ for activity. Unlike EC
1.1.1.41, isocitrate dehydrogenase (NAD+), oxalosuccinate can be used as a substrate. In eukaryotes, isocitrate dehydrogenase exists in two forms: an NAD+-linked enzyme found only in mitochondria and displaying allosteric properties, and a non-allosteric, NADP+-linked enzyme that is found in both mitochondria and cytoplasm [6]. The enzyme from some species can also use NAD+ but much more slowly [6,7].