阿特拉津降解菌LY-2的分离鉴定及其对污染土壤的修复  

Isolation and Identification of Atrazine-Degrading Bacterial Strain LY-2 and Its Bioremediation to Contaminated Soil

作　　者：李阳阳[1] 张金波[1] 沙君雪 史琛琛 迟宝岩 高继国[1] 李海涛[1] 刘荣梅[1] LI Yang-Yang;ZHANG Jin-Bo;SHA Jun-Xue;SHI Chen-Chen;CHI Bao-Yan;GAO Ji-Guo;LI Hai-Tao;LIU Rong-Mei(College of Life Science, Northeast Agricultural University, Harbin 150030, China)

机构地区：[1]东北农业大学生命科学学院,哈尔滨150030

出　　处：《农业生物技术学报》2018年第6期987-994,共8页Journal of Agricultural Biotechnology

基　　金：黑龙江省教育厅科学技术研究项目(No.12521021)

摘　　要：除草剂阿特拉津(2-氯-4-乙胺基-6-异丙胺基-1,3,5-三嗪,2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine,Atrazine)在很多国家普遍使用,对自然环境和人类健康造成威胁。本研究利用富集法,从黑龙江省哈尔滨市巴彦县施用多年阿特拉津的玉米地表层土中,分离出高效降解阿特拉津的菌株LY-2。LY-2以阿特拉津为唯一氮源,初步鉴定属于肠杆菌属(Enterobacter sp.)。PCR检测结果表明,LY-2含有阿特拉津降解相关的基因—阿特拉津氯水解酶基因(atrazine chlorohydrolase gene,atzA)、羟基阿特拉津脱乙胺基水解酶基因(hydroxyatrazine N-ethylaminohydrolase gene,atzB)和N-异丙基氰尿酰氨异丙氨基水解酶基因(N-isopropylammelide isopropylaminohydrolase gene,atzC)。LY-2在48 h内对100 mg/L阿特拉津降解率为98.7%;适宜温度为25~35℃,适宜酸碱度为p H 6~9;外加氮源没有降低该菌株对阿特拉津的降解率。土壤修复实验结果显示,培养7 d后,LY-2菌株对阿特拉津污染土壤(100 mg/kg)的降解率高达86.7%,培养14 d后,降解率高达90.1%。LY-2菌株在相对较短的时间内表现出良好的修复效果,在修复阿特拉津污染的土壤方面具有潜在的应用价值。Atrazine（2-chloro-4-ethylamino-6-isopropyl-amino-1,3,5-triazine） is widely used in many countries,and has great threat to the environment and human beings.In order to obtain a highly efficient atrazine-degrading bacteria,the present study isolated a bacterial strain（LY-2） which could use atrazine as a sole nitrogen source to grow by enrichment culture.The source was from the surface soil of maize field where atrazine had been used for many years.LY-2 was identified as Enterobacter sp.strain.It was the first reported Enterobacter sp.strain in detail that could degrade atrazine.The results of PCR test showed that LY-2 contained atrazine-degrading gene atzA,atzB,and atzC,which were involved in the degradation of atrazine to cyanuric acid.The strain LY-2 could degrade 98.7% atrazine（100 mg/L） within 48 h.The optimum temperature range of the strain was 25~35 ℃ and the optimum p H range was 6~9.Additional nitrogen sources did not affect the degradation of atrazine.The experiment of soil remediation showed that the highest degradation rate of the strain was 86.7% after incubation for 7 d,and the highest degradation rate of strain was90.1% after incubation for 14 d,the concentration of atrazine in contaminated soil was 100 mg/kg.The strain LY-2 shows good bioremediation effect in a relatively short period of time and has a better potential for bioremediation of atrazine-contaminated soil.

关 键 词：阿特拉津 肠杆菌 降解 生物修复 

分 类 号：S154.1[农业科学—土壤学] Q939.9[农业科学—农业基础科学]