title: Purification and properties of extremely thermostable glutamate dehydrogenases from two hyperthermophilic archaebacteria, Pyrococcus woesei and Pyrococcus furiosus.
abstract: Glutamate dehydrogenase (L-glutamate: NADP oxidoreductase, deaminating, EC 1.4.1.4) from the hyperthermophilic archaebacteria Pyrococcus woesei and P. furiosus were purified to homogeneity from crude extracts. The enzymes had similar enzymological properties: molecular mass, subunit structure, optimum pHs for the oxidative deamination and reductive amination, substrate specificity and coenzyme specificity as well as thermostability; the activity was not lost after incubation at 105 degrees C for 30 min. However, some differences were detected in resistance to urea denaturation and effects of salts on their activity and stability. The N-terminal 20 amino acid sequences of the two enzymes were identical.
authors.affiliation: Department of Chemistry, Kyoto University of Education, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ohshima
authors.forename: N
authors.initials: N
authors.lastname: Nishida
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism; D001105:Archaea / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D005969:Glutamate Dehydrogenase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007651:Keto Acids / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009243:NAD / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D000596:Amino Acids; D007651:Keto Acids; D009243:NAD; D009249:NADP; D005969:Glutamate Dehydrogenase