Yang S D, Vandenheede J R, Merlevede W
J Biol Chem. 1981 Oct 25;256(20):10231-4.
In previous reports (Yang, S. D., Vandenheede, J. R., Goris, J., and Merlevede, W. (1980) J. Biol. Chem. 255, 11759-11767; Vandenheede, J. R., Yang, S.-D., and Merlevede, W. (1981) J. Biol. Chem. 256, 5894-5900), we have described two slightly different purification procedures for the isolation of the inactive ATP-Mg-dependent protein phosphatase (FC) which could be activated by a protein activator (FA) in the presence of ATP-Mg. Although the two procedures consistently produced FC preparations that showed very similar polyacrylamide gel patterns, the specific activity of the purified enzymes varied considerably. The preparations characterized by a rather low specific activity could be stimulated up to 10-fold when a titrated amount of inhibitor-2 was included during the FA and ATP-Mg-mediated activation. Inhibitor-2, only recently implicated as an inactivating protein for activated FC (Vandenheede, J. R., Goris, J., Yang, S.-D., Camps, T., and Merlevede, W. (1981) FEBS Lett. 127, 1-3) has now been identified as a modulator protein, necessary for the reversible activation of the protein phosphatase.
在之前的报道中（杨，S.D.，范登海德，J.R.，戈里斯，J.，和默勒维德，W.（1980）《生物化学杂志》255，11759 - 11767；范登海德，J.R.，杨，S.-D.，和默勒维德，W.（1981）《生物化学杂志》256，5894 - 5900），我们描述了两种略有不同的纯化程序，用于分离无活性的ATP - Mg依赖性蛋白磷酸酶（FC），该酶在ATP - Mg存在下可被一种蛋白激活剂（FA）激活。尽管这两种程序始终产生的FC制剂在聚丙烯酰胺凝胶图谱上显示出非常相似的模式，但纯化酶的比活性差异很大。当在FA和ATP - Mg介导的激活过程中加入滴定剂量的抑制剂 - 2时，以相当低的比活性为特征的制剂可被刺激高达10倍。抑制剂 - 2，直到最近才被认为是激活的FC的一种失活蛋白（范登海德，J.R.，戈里斯，J.，杨，S.-D.，坎普斯，T.，和默勒维德，W.（1981）《欧洲生物化学学会联合会快报》127，1 - 3），现在已被确定为一种调节蛋白，是蛋白磷酸酶可逆激活所必需的。
