Catalyzes the conversion of L-glutamine and 2-oxoglutarate into two molecules of L-glutamate. 2 L-glutamate + NADP(+) = 2-oxoglutarate + H(+) + L-glutamine + NADPH Binds 1 [4Fe-4S] cluster. Optimum pH is 7.6. Amino-acid biosynthesis; L-glutamate biosynthesis via GLT pathway; L-glutamate from 2-oxoglutarate and L-glutamine (NADP(+) route): step 1/1. Energy metabolism; nitrogen metabolism. Aggregate of 4 catalytic active heterodimers, consisting of a large and a small subunit. Glutamine binds to the large subunit and transfers the amido group to 2-oxoglutarate that apparently binds to the small subunit.