Reaction of Toxic Bicyclic Phosphates with Acetylcholinesterases and α-Chymotrypsin
Reaction of Toxic Bicyclic Phosphates with Acetylcholinesterases and α-Chymotrypsin
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有毒双环磷酸酯与乙酰胆碱酯酶和 α-胰凝乳蛋白酶的反应
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发表时间：
1982
期刊：
影响因子：
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通讯作者：
M. Eto
中科院分区：
文献类型：
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作者：
Y. Ozoe;K. Mochida;M. Eto
一些有毒的双环磷酸盐（BPs）抑制乙酰胆碱酯酶（AChEs），但活性很弱。即使是最有效的抑制剂，4-硝基BP，抑制牛红细胞和家蝇头AChEs只有37%和38%，分别在1.5毫米。动力学分析表明，4-硝基BP的抑制活性差归因于不仅对AChEs的低亲和力，但也其磷酸化能力差。在BPs与丝氨酸酶α-胰凝乳蛋白酶反应的情况下也得到了类似的结果。尽管在碱性溶液中具有相对高的反应性，但BP在磷酸化一般碱催化的羟基基团中的活性远低于其他生物活性有机磷酯。这一事实表明，BPs的毒性作用不是由生物系统中关键位点的磷酸化引起的。
Some toxic bicyclic phosphates (BPs) inhibited acetylcholinesterases (AChEs), but the activity was very weak. Even the most potent inhibitor, 4-nitro BP, inhibited bovine erythrocyte and housefly head AChEs by only 37 and 38 per cent, respectively, at 1.5 mm. Kinetic analysis indicated that the poor inhibitory activity of 4-nitro BP is ascribed not only to the low affinity for AChEs but also to its poor phosphorylating ability. Similar findings were obtained in the case of the reaction of BPs with the serine enzyme α-chymotrypsin. Despite the relatively high reactivity in an alkaline solution, BPs are much less active than other bioactive organophosphorus esters in phosphorylating a general-base-catalyzed hydroxyl group. This fact suggests that the toxic action of BPs does not result from the phosphorylation of a critical site in biological systems.