Formulation: 50 mM Tris-HCl, pH 7.5, containing 200 mM sodium chloride, 5 mM β-mercaptoethanol, and 10% glycerol
Purity: ≥95% estimated by SDS-PAGE
Shelf life (days): 180
Notes: Isocitrate dehydrogenases (IDHs) are NAD+ and NADP+-dependent enzymes that catalyze the third step of the tricarboxylic acid cycle. IDHs catalyze oxidative decarboxylation of isocitrate producing α-ketoglutarate (α-KG) and carbon dioxide. IDH1 (cytosolic) and IDH2 (mitochondrial) are NADP+-dependent enzymes that catalyze reversible reactions. The IDH3 isoform, a NAD+-dependent multisubunit enzyme, is irreversible and allosterically regulated by a variety of positive (calcium, ADP, and citrate) and negative (ATP, NADH, and NADPH) effectors.{22137} IDH1 and IDH2 are mutated in >70% of lower grade gliomas.{22138} The most common IDH mutation, Arg132His, imparts new gain of function catalytic activity leading to the NADPH-dependent conversion of α-KG to 2-hydroxyglutarate.{22135,22156} Astrocytes expressing IDH1 R132H mutant have been shown to produce markedly increased levels of the R-2-hydroxyglutarate enantiomer, leading to transformation of cells through the HIF prolyl 4-hydroxylase, EGLN.{20681}