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研究了Ｃｏｒｙｎｅｂａｃｔｅｒｉｕｍｇｌｕｔａｍｉｃｕｍ菌的天冬氨酸激酶（下简称为Ａｓｐ激酶）的部分纯化和某些特性。由于使用了添加硫酸铵和天冬氨酸的磷酸缓冲液，成功地获得了纯度较高、比活力提高１０～１５倍的Ａｓｐ激酶。当硫酸铵以０．１～０．８Ｍ浓度添加时，对酶活性的促进作用最强。对照研究了一些氨基酸对脱盐酶液和Ｇ－２００酶液的不同影响，在５２４菌株种子培养时，以２０小时种龄，２５０ｍｌ／Ｌ装量，激酶的比活力最高；发酵培养时，２３小时后酶活力开始明显下降，但可随尿素的添加而回升。Ａｓｐ激酶的动力学常数是：ＫＡＳＰ为２０１．４ｍＭ；ＫＡＴＰ为３６．４ｍＭ；最适ｐＨ为９．０－９．５；Ｌ－苏氨酸Ｌ－苏氨酸＋Ｌ－赖氨酸对该酶的抑制，与ＡＳＰ是竞争性的，而与ＡＴＰ则是混合性的。
The partial purification and certain properties of the aspartokinase of Corynebacterium glutamicum (hereinafter referred to as Asp kinase) were studied. Due to the use of phosphate buffer with ammonium sulfate and aspartate, Asp kinases with higher purity and 10 to 15 times more specific activity were successfully obtained. When ammonium sulfate is added at the concentration of 0.1 ~ 0.8M, the promotion of enzyme activity is the strongest. The different effects of some amino acids on the enzyme solution and the G-200 enzyme solution were investigated. When the strain 524 was cultured for 20 hours, the specific activity of kinases was the highest at 20-hour seedling age and 250 ml / L. During the fermentation, After the enzyme activity began to decline significantly, but with the addition of urea and rebound. Kinetic constants for Asp kinase are: KASP 201.4 mM; KATP 36.4 mM; optimum pH 9.0-9.5; L-threonine L-threonine + L-lysine for this enzyme Of inhibition, is competitive with ASP, and is mixed with ATP.