| Glutamic-oxaloacetic transaminase was purified from tobacco by ammonium sulfate, DEAE-Sepharose Fast Flow ion exchange chromatography, Sephadex G -100 gel filtration. And the characteristics were intensively studied. The optimum reaction conditions of GOT were gained: temperature 37益, pH 8.5~9.0. Mn2+, Zn2+, Fe2+ could activate the activity of GOT, the best amino donor was L-Aspartate. The maximum reaction rate of the enzymatic reactions was 0.575 滋mol/L窑min, and the Michaelis constant of LAspartate and a-ketoglutarate were 0.929 滋mol/L and 0.105 滋mol/L. The study also showed that GOT couldn't catalyze the reaction between pyridoxine and pyridoxal, which could prove that there was another transaminase to catalyze the reaction in higher plants. |
