Thomas C D, Modha J, Razzaq T M, Cullis P M, Rivett A J
Department of Biochemistry, University of Leicester, UK.
Gene. 1993 Dec 22;136(1-2):237-42. doi: 10.1016/0378-1119(93)90471-e.
Lon protease from Escherichia coli is an ATP-dependent protease which plays important roles in regulating the levels of specific proteins and in eliminating abnormal proteins. A major problem of working with Lon protease, the inability to substantially overproduce the enzyme, has been overcome by placing the lon gene under the control of an inducible trp promoter within a copy-number-controllable plasmid. Induction resulted in higher levels of production of the protease (approximately 100 micrograms/ml of cell culture) than were previously possible. The enzyme has been purified to apparent homogeneity and shown to possess the characteristic ATP-dependent proteolytic activity. Sequence verification during DNA manipulations revealed differences from two previously published sequences for the lon gene.
来自大肠杆菌的Lon蛋白酶是一种依赖ATP的蛋白酶，在调节特定蛋白质水平和清除异常蛋白质方面发挥着重要作用。使用Lon蛋白酶的一个主要问题是无法大量过量生产该酶，通过将lon基因置于拷贝数可控质粒中可诱导的trp启动子的控制下，这一问题已得到解决。诱导导致蛋白酶的产量高于以往水平（约100微克/毫升细胞培养物）。该酶已被纯化至表观均一，并显示具有典型的依赖ATP的蛋白水解活性。DNA操作过程中的序列验证揭示了与之前发表的两个lon基因序列存在差异。
