Abdel-Ghany M, Raden D, Racker E, Katchalski-Katzir E
Section of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY 14853.
Proc Natl Acad Sci U S A. 1988 Mar;85(5):1408-11. doi: 10.1073/pnas.85.5.1408.
A synthetic random polymer of threonine and glutamate (1:4.4) is readily phosphorylated by protein kinase P but not by five other protein-serine (threonine) kinases. A synthetic random polymer of serine and arginine (1:3) is readily phosphorylated by protein kinase A and protein kinase C but not by protein kinase P. Although the amino acid sequences surrounding the phosphorylated serine (threonine) residue have been demonstrated in studies with small synthetic polypeptides to be decisive factors in the rate at which they are phosphorylated, the findings with the large synthetic polypeptides suggest that in the case of proteins the size, the tertiary structure, and particularly the electrostatic interactions are equally or more important contributing factors. Syringomycin, a toxin from Pseudomonas syringae, and polymyxin B, from Bacillus polymyxa, stimulate protein kinase P, strongly inhibit protein kinase C, and have no effect on protein kinase A. Basic polypeptides with high lysine content are phosphorylated by ATP nonenzymatically.
苏氨酸和谷氨酸的合成无规聚合物（1:4.4）很容易被蛋白激酶P磷酸化，但不会被其他五种蛋白丝氨酸（苏氨酸）激酶磷酸化。丝氨酸和精氨酸的合成无规聚合物（1:3）很容易被蛋白激酶A和蛋白激酶C磷酸化，但不会被蛋白激酶P磷酸化。尽管在对小型合成多肽的研究中已证明，磷酸化丝氨酸（苏氨酸）残基周围的氨基酸序列是其磷酸化速率的决定性因素，但对大型合成多肽的研究结果表明，对于蛋白质而言，大小、三级结构，尤其是静电相互作用同样重要或更为重要。丁香霉素（一种来自丁香假单胞菌的毒素）和多粘菌素B（来自多粘芽孢杆菌）可刺激蛋白激酶P，强烈抑制蛋白激酶C，对蛋白激酶A则无影响。高赖氨酸含量的碱性多肽可被ATP非酶促磷酸化。
