Glutamate Synthetase in Developing Cotyledons of Pisum sativum

Abstract

Glutamate synthetase (glutamine[amide]:alpha ketoglutarate amino transferase oxidoreductase) activity has been demonstrated in the developing cotyledons of Pisum sativum L. cv. Burpeeana. The enzyme appears to be soluble and is specific for glutamine as amide donor. The enzyme activity is greater with NADH than with NADPH as electron donor.It is suggested that glutamate synthetase in the developing cotyledon provides a mechanism by which the amide nitrogen of glutamine, from the translocatory stream, is converted into the amino nitrogen of glutamate; transamination reactions involving this synthesized glutamate could provide the amino groups for the biosynthesis of the seed protein amino acids.