恶臭假单胞菌XP12对拟除虫菊酯类农药的酶促降解特性及其应用研究  

Pseudomonas Putida XP12’s enzymatic degradation in pyrethroid pesticides and its application study

作　　者：解开治[1] 徐培智[1] 陈建生[1] 唐拴虎[1] 张发宝[1] 黄旭[1] 严超[1] 黄巧义[1] 

机构地区：[1]广东省农科院土壤肥料研究所/广东省农产品质量安全公共研究平台,广东广州510640

出　　处：《广东农业科学》2009年第12期156-160,共5页Guangdong Agricultural Sciences

基　　金：广东省教育部产学研结合项目(2007B090400101);广州市农业局招标项目(GZCQ0602FG001A);广东省农科院土壤肥料研究所所长基金项目(2008-szjj-02)

摘　　要：试验选用使用量较大、毒性较强、不易自然降解的高效氯氰菊酯、溴氰菊酯和高效氯氟氰菊酯作为参试农药,对一株能高效降解拟除虫菊酯类农药的恶臭假单胞菌XP12进行深入的研究,以期了解该菌株在拟除虫菊酯类农药的生物降解体系中酶的分布特征、酶促降解的动力学特征。结果表明:对拟除虫菊酯类农药起催化作用的酶属于组成型胞内酶,反应pH值为6.5～8.0时,降解酶对高效氯氰菊酯、溴氰菊酯和高效氯氟氰菊酯的降解率都在70%左右,最适反应pH值为7.5;反应温度在25～40℃时,降解率在70%以上,最适反应温度为30℃。在最适反应pH和温度条件下,降解酶粗酶液对高效氯氰菊酯、溴氰菊酯和高效氯氟氰菊酯的Km分别为42.78、50.64和77.90 nmol/mL,Vmax分别为12.05、10.31和16.39 nmol/min。粗酶液在叶类蔬菜上拟除虫菊酯类农药的降解也有明显效果,对高效氯氰菊酯、溴氰菊酯和高效氯氟氰菊酯的降解率分别为93.3%、85.2%、83.5%。The experiment adopts Beta-cypermethrin, Dehamethrin and Cyhalothrin, which are widely used, highly toxic and hard to be degraded, as trial pesticides and further studies a strain of Pseudomonas Putida XP12, which can effectively degrade Pyrethroid Pesticides, to get to know enzymatic distribution of this strain in biodegradation system of Pyrethroid Pesticides and dynamic characteristics of enzymatic degradation. The result proves that the enzyme, which has catalysis in Pyrethroid Pesticides, is a kind of constitutive intracellular enzyme. When reaction ph varies between 6.5 and 8.0, degradation rate of degrading enzyme in Beta-cypermethrin, Dehamethrin and Cyhalothrin reaches about 70% and optimum reaction ph is 7.5; when temperature varies between 25℃ and 40℃ and degradation rate is above 70%, temperature of optimum reaction is 30℃. With optimum reaction ph and temperature, crude enzyme liquid＇s Km of degrading enzyme in Beta-cypermethrin, Dehamethrin and Cyhalothrin is respectively 42.78 nmol/mL, 50.64 nmol/mL and 77.90 nmol/mL, and Vmax is respectively 12.05nmol/min, 10.31nmol/min and 16.39 nmol/min. Crude enzyme liquid also has obvious degradation effect on Pyrethroid Pesticides of leaf vegetable and its degradation rate in Beta-cypermethrin, Dehamethrin and Cyhalothrin is respectively 93.3%, 85.2% and 83.5%.

关 键 词：恶臭假单胞菌XP12 拟除虫菊酯类农药 降解酶 酶促降解 

分 类 号：Q55[生物学—生物化学] Q939.9