2 L-glutamate + NADP(+) = 2-oxoglutarate + H(+) + L-glutamine + NADPH Binds 1 [3Fe-4S] cluster. Activity is stimulated by unphosphorylated GarA. Amino-acid biosynthesis; L-glutamate biosynthesis via GLT pathway; L-glutamate from 2-oxoglutarate and L-glutamine (NADP(+) route): step 1/1. Interacts with unphosphorylated GarA. Was identified as a high-confidence drug target. Belongs to the glutamate synthase family.