Glutaminase catalyzes the hydrolysis of glutamine to glutamic acid and plays a key role in nitrogen metabolism. Catalyzes the hydrolysis not only of L-glutamine but also of D-glutamine. H2O + L-glutamine = L-glutamate + NH4(+) Activity is inhibited by about 80% in the presence of 18% sodium chloride. Optimum pH is 9.0. Optimum temperature is 37-45 degrees Celsius. In the fermentation of soy sauce, the traditional Japanese seasoning, glutaminase is one of the most important enzymes in flavor enhancement as it converts glutamine to glutamic acid. Belongs to the fungal glutaminase gtaA family. Extended N-terminus.