Further definition of the substrate specificity of the alpha-herpesvirus protein kinase and comparison with protein kinases A and C.
Further definition of the substrate specificity of the alpha-herpesvirus protein kinase and comparison with protein kinases A and C.
复制标题
α-疱疹病毒蛋白激酶底物特异性的进一步定义以及与蛋白激酶 A 和 C 的比较。
DOI：
10.1016/0167-4889(91)90210-o
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
L. Pinna
中科院分区：
文献类型：
--
作者：
D. Leader;A. D. Deana;F. Marchiori;F. Purves;L. Pinna
伪狂犬病病毒蛋白激酶偏好在靶丝氨酰基或苏氨酰基残基的氨基末端侧含有乙酰基残基的模型底物。我们在实验中使用一系列新的合成模型肽更精确地定义了这种底物特异性。当RnASVA型底物中N-乙酰基残基的数目从2个变化到4个时，发现具有4个N-乙酰基残基的肽构成最佳底物，尽管在N-乙酰基残基的数目从2个增加到3个时看到Km的最显著降低。在R4 AmSVA型肽中研究了从零到三个“间隔基”丙氨酰残基的数量变化的效果，发现具有一个丙氨酰残基的肽是最好的底物，使得R4 X成为该酶的最佳氨基末端环境。用单纯疱疹1型蛋白激酶观察到类似的底物特异性。就氨基末端碱性残基的数量和位置而言，蛋白激酶C被发现与病毒酶具有非常相似的底物偏好;但是，与病毒蛋白激酶不同的是，它还需要最佳肽底物中的羧基末端碱性残基，并且可以容忍赖氨酰取代乙酰基残基。环AMP依赖性蛋白激酶，像病毒酶，具有有利的动力学常数，这一系列的肽，但不同于后者能够催化磷酸化的肽与两个至四个乙酰基残基具有类似的效率。以羽扇豆碱Y1蛋白为底物的研究表明，当存在合适的氨基端乙酰基决定簇时，伪狂犬病病毒蛋白激酶可以耐受其靶残基羧基端侧的乙酰基残基。在这方面，病毒蛋白激酶类似于蛋白激酶C，但不同于环AMP依赖性蛋白激酶，后者不能耐受这种羧基末端碱性残基。底物特异性与模型肽的伪狂犬病病毒蛋白激酶在体外和体内磷酸化蛋白质的能力的关系进行了讨论。
The pseudorabies virus protein kinase prefers model substrates containing arginyl residues on the amino-terminal side of a target seryl or threonyl residue. We have defined this substrate specificity more precisely in experiments using a new series of synthetic model peptides. When the number of arginyl residues was varied from two to four in substrates of the type RnASVA it was found that peptides with four arginyl residues constituted the best substrates, although the most marked decrease inKmwas seen on increasing the number of arginyl residues from two to three. The effect of varying the number of ‘spacer’ alanyl residues from zero to three was investigated in peptides of the type R4AmSVA, and the peptide with one alanyl residue was found to be the best substrate, making R4X the optimal amino-terminal environment for this enzyme. A similar substrate specificity was observed with the herpes simplex type 1 protein kinase. Protein kinase C was found to have a quite similar substrate preference to the viral enzyme as far as the number and position of the amino-terminal basic residues was concerned; but, unlike the viral protein kinase, it also requires carboxy-terminal basic residues in optimal peptide substrates, and can tolerate the substitution of lysyl for arginyl residues. The cyclic AMP-dependent protein kinase, like the viral enzyme, had favourable kinetic constants for this series of peptides, but differed from the latter in being able to catalyze the phosphorylation of the peptides with two to four arginyl residues with similar efficiency. Studies with the protein, clupeine Y1, as substrate indicated that the pseudorabies virus protein kinase can tolerate arginyl residues on the carboxyl-terminal side of its target residue when there are suitable amino-terminal arginyl determinants. In this respect the virus protein kinase resembled protein kinase C but differed from the cyclic AMP-dependent protein kinase which cannot tolerate such carboxyl-terminal basic residues. The relationship of substrate specificity with model peptides to the ability of the pseudorabies virus protein kinase to phosphorylate proteins in vitro and in vivo is discussed.