毒死蜱降解菌株Bacillus latersprorus DSP的降解特性及其功能定位  

CHARACTERISTICS AND FUNCTION OF BACILLUS LATERSPRORUS DSP IN DEGRADING CHLORPYRIFOS

作　　者：王晓[1] 楚小强[1] 虞云龙[1] 方华[1] 陈洁[1] 宋凤鸣[1] 

机构地区：[1]浙江大学农业与生物技术学院植保系,杭州310029

出　　处：《土壤学报》2006年第4期648-654,共7页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(20377036;30230250);国家重点基础研究发展规划973项目(2002CB410806);杭州市科技专项项目(2002112A08)资助

摘　　要：从土壤中分离到一株能有效降解毒死蜱的细菌DSP,该分离株鉴定为侧芽孢杆菌(Bacillus lat-ersprorus)。在纯培养条件下测定了分离株DSP对毒死蜱的降解性能。在接种量为菌浓度OD415=0.2,pH 7.0、25℃条件下,测得1、10 mg L-1毒死蜱的降解符合一级动力学特征,其降解半衰期分别为1.48 d、5.00 d,100mg L-1毒死蜱对DSP菌有明显的抑制作用;分离株DSP在不同pH及温度下对毒死蜱的降解作用为pH 7.0>pH 5.0>pH 9.0,35℃>25℃>15℃。该菌株含有一个20 kb左右的质粒,通过吖啶橙与升温法对质粒消除实验证实,随着质粒的丢失,菌株利用毒死蜱的能力也丧失,用热击法和CaCl2法将菌株质粒转入大肠杆菌JM109和质粒消除处理的DSP-菌中,随着质粒的获得,这些转化子获得了降解毒死蜱的能力。研究结果表明,Bacillus latersprorusDSP降解毒死蜱的功能和质粒有关。A bacterial strain Bacillus latersprorus DSP capable of degrading chlorpyrifos was isolated from soil. Degradation characteristics of chlorpyrifos by the strain DSP were investigated in pure culture system under conditions of pH 7.0, 25 ℃ and biomass of OD415 0.2. The half-life of chlorpyrifos at concentrations of 1 and 10 mg L^- 1 was measured to be 1.48 d and 5.00 d, respectively. The chemical showed obvious inhibitive effect on degradation capability of the strain, when its concentration reached as high as 100 mg L^- 1. The degradation rate of chlorpyrifos by the Strain DSP was affected by pH and temperature showing an order of pH 7.0 〉 pH 5.0 〉 pH 9.0, and of 35℃ 〉 25℃ 〉 15℃, respectively. A plasmid with a size of approximately 20 kb was found in Strain DSP. The strain lost its ability to degrade chlorpyrifos when the plasmid was removed by acridine orange and heating. When the plasmid was transferred into Escherichia coli JM109 and back into plasmid-removed DSP the transformants obtained the ability to degrade chlorpyrifos. These observations indicated that the plasmid of Strain DSP is responsible for the degradation of chlorpyrifos.

关 键 词：毒死蜱 降解质粒 侧芽孢杆菌 土壤 

分 类 号：S154.39[农业科学—土壤学]