Brain acetylcholinesterase (AChE; EC 3.1.1.7) from peacock bass (Cichla ocellaris) was characterized and the effect of organophosphorus and carbamate pesticides as well as ions and heavy metals was evaluated. The kinetic parameters K(m) and V(max) were determined as 0.769 mM and 0.189 U/mg of protein respectively. Optimal pH and temperature were found to be 8.0 and 45°C. The enzyme retained approximately half of the activity after incubation at 50°C for 30 min. Total cholinesterase activity on brain of this species can be ascribed to AChE according to selective inhibitors analysis (neostigmine, eserine and BW284c5 reduced its activity whereas no effect was noticed for Iso-OMPA). Seven pesticides (five organophosphates: dichlorvos, diazinon, chlorpyrifos, temephos, tetraethyl pyrophosphate - TEPP and two carbamates: carbaryl and carbofuran) showed inhibitory effects on C. ocellaris AChE. However, the strongest effect was observed with carbofuran (IC(50)=0.21 μM and K(i)=2.57 × 10(-3) μM). The following ions (1 mM) showed to inhibit its activity (decrescent order): Hg(2+)>As(3+)>Cu(2+)>Zn(2+). EDTA(2-) did not affect enzyme activity. The present study provides assay conditions and data to suggest this enzyme as in vitro biomarker of organophosphorus and carbamate pesticides in routine environmental screening programs.

译文

:表征了孔雀鲈(Cichla ocellaris)的脑乙酰胆碱酯酶(AChE; EC 3.1.1.7),并评估了有机磷和氨基甲酸酯农药以及离子和重金属的影响。动力学参数K(m)和V(max)分别确定为0.769 mM和0.189 U / mg蛋白质。发现最佳pH和温度为8.0和45℃。在50°C孵育30分钟后,该酶保留了大约一半的活性。根据选择性抑制剂分析,该物种在大脑上的总胆碱酯酶活性可以归因于AChE(新斯的明,鸟氨酸和BW284c5降低了其活性,而Iso-OMPA则未见效果)。七种农药(五种有机磷酸酯:敌敌畏,二嗪农,毒死rif,坦弗索斯,焦磷酸四乙酯-TEPP和两种氨基甲酸酯:西维因和呋喃呋喃)显示出对C. ocellaris AChE的抑制作用。然而,用呋喃丹观察到效果最强(IC(50)= 0.21μM,K(i)= 2.57×10(-3)μM)。以下离子(1 mM)显示出抑制其活性的作用(降序):Hg(2)> As(3)> Cu(2)> Zn(2)。 EDTA(2-)不会影响酶的活性。本研究提供了测定条件和数据,表明该酶是常规环境筛选程序中有机磷和氨基甲酸酯农药的体外生物标志物。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录