THIOPHOSPHORYLATED SUBSTRATE-ANALOGS ARE POTENT ACTIVE-SITE-DIRECTED INHIBITORS OF PROTEIN-TYROSINE PHOSPHATASES
THIOPHOSPHORYLATED SUBSTRATE-ANALOGS ARE POTENT ACTIVE-SITE-DIRECTED INHIBITORS OF PROTEIN-TYROSINE PHOSPHATASES
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DOI：
10.1006/abio.1994.1545
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发表时间：
1994-11-15
影响因子：
2.9
通讯作者：
INGEBRITSEN, TS
中科院分区：
文献类型：
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作者：
HIRIYANNA, KT;BAEDKE, D;INGEBRITSEN, TS
硫代磷酸酪氨酰蛋白和肽底物类似物被发现是有效且特异性的蛋白酪氨酸磷酸酶抑制剂，IC(50)在0.2-30μM范围内。这些类似物基于高反应性底物，包括还原甲酰胺甲基化和马来酰化溶菌酶的硫代磷酸酪氨酰形式以及基于溶菌酶、α(s2)-酪蛋白和酪氨酸磷酸化位点的肽。血小板衍生生长因子受体。这些类似物抑制细胞内和跨膜类以及从原核生物（小肠耶尔森氏菌）到人类的多种物种的蛋白质酪氨酸磷酸酶。给定类似物对磷酸酶活性的抑制程度随磷酸酶种类的不同而变化。相反，蛋白激酶和蛋白丝氨酸/苏氨酸磷酸酶并未受到这些类似物的显着影响。以大鼠脑蛋白酪氨酸磷酸酶1为原型，研究了抑制机制。这些研究表明，抑制是快速且可逆的，并且本质上是竞争性的。各种硫代磷酸酪氨酰类似物的抑制作用的 K-i 通常与相应磷酸化底物的表观 K-m 成正比。未磷酸化的底物分子通常是比相应的硫代磷酸酪氨酰底物类似物弱得多的抑制剂。总而言之，这些结果表明了一种活性定点抑制机制。这些特异性抑制探针可用于研究底物结合机制以及各种蛋白质酪氨酸磷酸酶的生理作用。 (C) 1994 年学术出版社
Thiophosphotyrosyl protein and peptide substrate analogs were found to be potent and specific protein-tyrosine phosphatase inhibitors with IC(50)s in the range of 0.2-30 mu M. The analogs were based on highly reactive substrates and included thiophosphotyrosyl forms of reduced carboxamidomethylated and maleylated lysozyme and peptides based on tyrosine phosphorylation sites of lysozyme, alpha(s2)-casein, and platelet-derived growth factor receptor. These analogs inhibited protein-tyrosine phosphatases from both the intracellular and transmembrane classes and from a variety of species ranging from a prokaryote (Yersinia enterolitica) to man. The extent of inhibition of phosphatase activity by a given analog varied with the phosphatase species. In contrast, protein kinases and protein-serine/threonine phosphatases were not significantly affected by these analogs. The mechanism of inhibition was investigated using rat brain protein-tyrosine phosphatase-1 as a prototype. These studies indicated that the inhibition was rapid and reversible and was competitive in nature. The K-i for inhibition by various thiophosphotyrosyl analogs was generally proportional to the apparent K-m for the corresponding phosphorylated substrates. Unphosphorylated substrate molecules were generally much weaker inhibitors than the corresponding thiophosphotyrosyl substrate analogs. Taken together these results point to an active site-directed mechanism for inhibition. These specific inhibitory probes could be used to study substrate binding mechanisms as well as physiological roles of various protein-tyrosine phosphatases. (C) 1994 Academic Press, Inc.