title: NADP-specific isocitrate dehydrogenase from Escherichia coli. V. Multiple forms of the enzyme.
abstract: Two forms of NADP-specific isocitrate dehydrogenase (threo-DS-isocitrate: NADP+ oxidoreductase (decarboxylating), EC 1.1.1.42) in Escherichia coli have been resolved by polyacrylamide gel isoelectric focusing and electrophoresis. Incubation of the enzyme with Mn2+ plus isocitrate prior to focusing resulted in the formation of an additional form of the enzyme, presumably the enzyme-manganese-isocitrate complex. Glycerol, a cryoprotectant used to stabilize the enzyme during purification and storage, also stabilized in during focusing, but was not necessary during electrophoresis. Thin-layer gel filtration did not reveal any differences in molecular weight between the different species of isocitrate dehydrogenase.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D004355:Drug Stability; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000201:enzymology*; D005990:Glycerol; D007521:Isocitrate Dehydrogenase; D007523:Isocitrates; D007525:Isoelectric Focusing; D007527:Isoenzymes; D046911:Macromolecular Substances; D008345:Manganese; D008970:Molecular Weight; D009249:NADP / Q000494:pharmacology
chemical_list: D007523:Isocitrates; D007527:Isoenzymes; D046911:Macromolecular Substances; D008345:Manganese; D009249:NADP; D007521:Isocitrate Dehydrogenase; D005990:Glycerol