A flavoprotein (FMN). The reaction takes place in the direction of L-glutamate production. The protein is composed of two domains, one hydrolysing L-glutamine to NH3 and L-glutamate (cf. EC 3.5.1.2, glutaminase), the other combining the produced NH3 with 2-oxoglutarate to produce a second molecule of L-glutamate (cf. EC 1.4.1.2, glutamate dehydrogenase).