Glutamate dehydrogenase was purifiedfrom thecrudeextract of Pseudomonas pseudoal caligenes.Theenzyme had a molecular weight of 290 000 and was composed of six subunits with identical molecular weightof47 000 . The enzyme was highly specific for NADP(H) and the sub strates.The biochemicalpropertiessuch askineticparametersand heatstability werealsoexamined. The purified GDHshowed considerableloss ofactivity uponfreezing.