舞毒蛾(Lymantria dispar)酚氧化酶的酶学特征及有机溶剂对其活性的影响  

THE PROPERTIES OF THE PHENOLOXIDASE(PO) FROM LYMANTRIA DISPARAND EFFECTS OF ORGANNIC SOLVENTS ON THE ACTIVITY OF PO

作　　者：赵燕[1,2] 曹露凡[1] 刘奎伟[1] 刘慧慧[1] 崔晶晶[1] 周成刚[1,3] 罗万春[1] 

机构地区：[1]山东农业大学植物保护学院,山东泰安271018 [2]济南市林业局,济南250099 [3]山东省林业有害生物防控工程技术研究中心

出　　处：《山东农业大学学报（自然科学版）》2011年第1期11-16,共6页Journal of Shandong Agricultural University：Natural Science Edition

基　　金：国家自然科学基金资助项目"昆虫酚氧化酶抑制剂的抑制机理及其构效关系"(30571237)

摘　　要：经35%饱和度硫酸铵分级沉淀,将舞毒蛾(Lymantria dispar)酚氧化酶部分纯化。测定该酶最适pH值为6.5,pH在6.5～7.5范围内酶保持稳定的活力。最适温度为35℃,当温度低于25℃时,酶具有稳定的活力。以L-多巴、邻苯二酚和焦性没食子酸为底物时,测定酚氧化酶对底物的专一性,结果表明其Km值分别为3.19、10.74和19.26 mmol.L-1。本实验还研究了有机溶剂对酶活力的影响,结果表明甲醇、乙醇、丙酮和二甲苯对舞毒蛾酚氧化酶都有持续的抑制作用,其IC50分别为0.450、.430、.41和0.13 mmol.L-1。The kinetic properties of phenoloxidase （PO, EC. 1.14.18.1 ） from Lymantria dispar, a forestry insect, were determined after the enzyme was partially purified by 35% staturated （NH4） 2SO4. The properties of PO showed that the optimum pH was 6.5 and the enzyme had a stable activity if the pH reaction system from 6. 5 to 7.5, the optimum temperature was 35 ~C, and the enzyme had a stable activity if the temperature reaction system less than 25 ~C, using catechol as substrate. The kinetic parameter for the oxidation of L - DOPA, cate- chol and pyrogallol by PO was determined, the Km was 3.19,10.74 and 19.26 mmol · L-1, respectively. The effects of some organic methanol, ethanol, acetone and dimethylbenzene solvents on the activity of PO were also studied in the present paper. The results showed that all of them had inhibitory effects on the enzyme activity. The IC50 （the inhibitor concent rations leading to 50 % activity lost） of methanol, ethanol and dimethylbenzene were estimated to be 0. 45 ,0. 43 ,0. 41 and 0.13 mmol · L^-1, respectively.

关 键 词：舞毒蛾 酚氧化酶 酶学特征 有机溶剂 

分 类 号：Q966[生物学—昆虫学]