Sakai K, Asahi M, Kobayashi T, Tanaka Y, Inazu T, Nakamura S, Yamamura H
Department of Biochemistry, Fukui Medical School, Japan.
Biochem Biophys Res Commun. 1989 Feb 15;158(3):1043-9. doi: 10.1016/0006-291x(89)92827-1.
Cytosolic protein-tyrosine kinase from porcine spleen (CPTK-40) is strongly activated by poly-L-lysine using bovine serum albumin, ovalbumin, phosphorylase b, calmodulin and H1 histone as substrate proteins. However, this polyamine inhibited the enzyme activities when myelin basic protein, tubulin and H2B histone were used as substrate proteins. These stimulatory and inhibitory effects on CPTK-40 are not specific for polylysine, but polyarginine and polyornithine have similar effects on this phosphorylation reaction. Effect of poly-basic amino acids on CPTK-40 seems to be mainly on the substrate proteins, rather than on the enzyme itself.
以牛血清白蛋白、卵清蛋白、磷酸化酶b、钙调蛋白和H1组蛋白作为底物蛋白时,来自猪脾脏的胞质蛋白酪氨酸激酶(CPTK - 40)会被聚-L-赖氨酸强烈激活。然而,当以髓鞘碱性蛋白、微管蛋白和H2B组蛋白作为底物蛋白时,这种多胺会抑制该酶的活性。对CPTK - 40的这些刺激和抑制作用并非聚赖氨酸所特有,聚精氨酸和聚鸟氨酸对该磷酸化反应也有类似作用。多碱性氨基酸对CPTK - 40的影响似乎主要作用于底物蛋白,而非酶本身。