Purification and characterization of the NADP-dependent glutamate dehydrogenase from Bacillus fastidiosus.
Ammonia assimilation in Bacillus fastidiosus proceeds via the NADP-dependent glutamate dehydrogenase. The enzyme, purified to homogeneity, is composed of identical subunits with a molecular weight of about 48,000 dalton. Presumably the enzyme is a hexamer. The enzyme is specific for NADP(H). The pH optima for the amination and deamination reactions are 7.7 and 8.6, respectively. The temperature optimum is 60 degrees C. Furthermore, temperature stability and apparent Km values for substrates of both the amination and deamination reactions were determined. Several metabolites were tested for their effect on the enzyme activity. Only malate and fumarate showed some inhibitory effect.
Op den Camp
H J
HJ
Department of Microbiology, Faculty of Science, University of Nijmegen, The Netherlands.
Liem
K D
KD
Meesters
P
P
Hermans
J M
JM
Van der Drift
C
C
D001407:Bacillus / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D005969:Glutamate Dehydrogenase / Q000302:isolation & purification* / Q000378:metabolism; D018086:Glutamate Dehydrogenase (NADP+); D006863:Hydrogen-Ion Concentration; D009243:NAD / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature
D009243:NAD; D009249:NADP; D005969:Glutamate Dehydrogenase; D018086:Glutamate Dehydrogenase (NADP+)