Alanine aminotransferase from Cucurbita moschata cotyledons

Alanine aminotransferase increased in pumpkin cotyledons duringgermination with the greatest increase occurring in green cotyledons.The enzyme was found in the soluble fraction and was inhibitedby NH₂OH and p-chloromercuribenzoate. Pyridoxal phosphate andglutathione or dithiothreitol overcame die respective inhibition.Dialysis of the enzyme reduced enzyme activity but the activitywas restored by the addition of pyridoxal phosphate. Alanineaminotransferase was proposed to play a major role in the synthesisof the alanine which occurs in pumpkin cotyledons during germination. (Received September 17, 1975; )