TITLE:
Using the RNA synthetic activity of glutamate dehydrogenase to illuminate the natural role of the enzyme
AUTHORS:
Godson O. Osuji, Wenceslaus C. Madu
KEYWORDS:
Peanut; Stoichiometric Mineral Salt Combinations; GDH Amination-Deamination Ratio; Glutamate Synthase; Amino Acid and Protein Yields ha–1
JOURNAL NAME:
Advances in Biological Chemistry,
Vol.2 No.4,
November
23,
2012
ABSTRACT: Glutamate Dehydrogenase (GDH; EC 1.4.1.2) catalyzes the reversible amination of α-ketoglutarate to glutamate, and the polymerization of nucleoside triphosphate(s) to RNA. But the natural role of the reversible amination reaction is the subject of an expanding conversation. The aim was to illuminate the natural role of GDH through its RNA synthetic activity. Stoichiometric combinations of mineral salts that targeted the GDH subunit compositions were applied to field-cultivated peanuts. GDH of seeds were made to synthesize RNA in the deamination and then in the amination direction. Free amino acids were analyzed by HPLC. Glutamate synthase (GOGAT) was assayed by photometry. Free amino acid yields in-creased from the control’s lowest (9.8 kg·ha–1) and amination-deamination ratio (0.05) through 12.0 - 23.0 kg·ha–1 in the K-, N+K+P+S-, Pi-, N+S-, S-treated peanuts with amination-deamination ratios between 0.6 and 10.0 until at the P+K-treated peanut which had the highest amino acid yield (52.4 kg·ha–1) and the highest amination-deamination ratio (61). The Km and Vmax values of GOGAT were within the normal range. Yields of free amino acids resulting from GDH aminating activity increased from