title: The NAD-dependent glutamate dehydrogenase from Dictyostelium discoideum: purification and properties.
abstract: The NAD-dependent glutamate dehydrogenase (GDH) from Dictyostelium discoideum was purified 1101-fold with a yield of 23.4%. The enzyme has an apparent Mr of 356 kDa, determined using Sephacryl S400, and a subunit molecular weight of 54 kDa on SDS-polyacrylamide gel electrophoresis. The Kms for alpha-ketoglutarate, NADH, and NH4+ are 0.36 +/- 0.03 mM, 16.0 +/- 0.1 microM, and 34.5 +/- 2.7 mM, respectively. The purified enzyme has a pH optimum of pH 7.25-7.5. At 0.1 mM, ADP and AMP stimulate GDH activity 25 and 102%, respectively. Half-maximal activity in the presence of 0.1 mM AMP for alpha-ketoglutarate, NADH, and NH4+ is reached at 2.3 +/- 0.1 mM, 71.4 +/- 5.5 microM, and 27.9 +/- 3.6 mM, respectively.
authors.affiliation: School of Biological Sciences, Flinders University of South Australia, Adelaide.
authors.forename: F
authors.initials: F
authors.lastname: Pamula
authors.forename: J F
authors.initials: JF
authors.lastname: Wheldrake
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D000249:Adenosine Monophosphate / Q000494:pharmacology; D000643:Ammonium Chloride / Q000378:metabolism; D000818:Animals; D004023:Dictyostelium / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects; D005969:Glutamate Dehydrogenase / Q000737:chemistry / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007656:Ketoglutaric Acids / Q000378:metabolism; D007700:Kinetics; D009243:NAD / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D007656:Ketoglutaric Acids; D000643:Ammonium Chloride; D009243:NAD; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate; D005969:Glutamate Dehydrogenase