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从类产碱假单胞菌纯化出电泳纯的谷氨酸脱氢酶，用聚丙烯酰胺梯度凝胶电泳和ＳＤＳ－聚丙烯酰胺凝胶电泳测得分子量为２９０ ｋＤ，亚基分子量为４７ ｋＤ，提示该酶为六聚体．该酶对ＮＡＤＰ（Ｈ）和底物均具有高度专一性，对谷氨酸、α－酮戊二酸及ＮＡＤＰ＋ 的Ｋｍ 值分别为：２８ ｍ ｍ ｏｌ／Ｌ、１．２ｍ ｍ ｏｌ／Ｌ及０．０６３ ｍ ｍ ｏｌ／Ｌ．用Ｈｉｌｌ作图法求得酶对ＮＨ＋４ 和ＮＡＤＰＨ 的［Ｓ］０．５分别为２４ ｍ ｍ ｏｌ／Ｌ和０．０３７ ｍ ｍ ｏｌ／Ｌ．最适反应温度为５０℃，催化氨化反应和脱氨反应的最适ｐＨ 分别为８．０和８．８，在热稳定性方面不及嗜热细菌的谷氨酸脱氢酶稳定．提纯的谷氨酸脱氢酶在低温（４℃）条件下，可在Ｔｒｉｓ－ＨＣｌ缓冲液中贮存半年以上，活力无明显下降，冷冻则可导致纯酶液迅速失活．氮源对菌体谷氨酸脱氢酶水平有显著影响．
Purified pure glutamate dehydrogenase from Pseudomonas pseudoalcaligenes, with a molecular weight of 290 kD and a molecular weight of 47 kD by polyacrylamide gradient gel electrophoresis and SDS-polyacrylamide gel electrophoresis , Suggesting that the enzyme is a hexamer. The enzyme is highly specific for NADP (H) and substrate with Km values for glutamic acid, alpha-ketoglutarate and NADP + of 28 m mol / L and 1.2 m mol / L, respectively And 0.063 m mol / L. The [S] 0.5 for NH + 4 and NADPH was calculated as 24 m mol / L and 0.037 m mol / L, respectively, using Hill plotting. The optimum reaction temperature was 50 ℃, the optimum pH of catalytic ammonification and deamination reaction were 8.0 and 8.8, respectively, which was less stable than the thermophilic bacteria glutamate dehydrogenase in thermal stability. Purified glutamate dehydrogenase at low temperature (4 ℃) conditions, can be stored in Tris-HCl buffer for more than six months, no significant decline in vitality, freezing can lead to rapid inactivation of pure enzyme solution. Nitrogen source has a significant effect on the level of glutamate dehydrogenase.