甲基对硫磷降解菌的分离鉴定及降解特性研究  

Study on isolating and characterizing HS-MP12-a strain capable of degrading methyl parathion

作　　者：高强[1] 邓灵福[1] 郑永良[1] 熊丽[1] 罗勤[1] 肖文精[2] 刘德立[1] 

机构地区：[1]华中师范大学生命科学学院,武汉430079 [2]华中师范大学农药与化学生物学教育部重点实验室,武汉430079

出　　处：《安全与环境学报》2007年第3期22-25,共4页Journal of Safety and Environment

基　　金：科技部重大基础研究项目(2004CCA00100);武汉市重点科技攻关项目(20062001018)

摘　　要：从湖北仙桃农药厂附近长期受农药污染的土壤中分离出1株甲基对硫磷降解菌HS-MP12,该菌能利用甲基对硫磷(MP)和对硝基苯酚(PNP)作为唯一的碳源、氮源生长。在24h内,HS-MP12对起始质量浓度为500mg/L和200mg/L的MP降解率分别为86.8%和95.7%,对起始质量浓度为200mg/L的PNP的降解率为92.3%,测定条件为:pH值6,温度30℃。HS-MP12经过形态观察、生理生化鉴定、16SrDNA序列测定和同源性分析,初步鉴定HS-MP12菌株为蜡状芽孢杆菌(Bacilluscereus)。实验结果表明,HS-MP12在降解MP时,没有代谢中间产物对硝基苯酚的积累,推测可能存在不同的降解途径。In this paper, we would like to introduce our experience on isolating a strain named HS-MP12 capable of degrading methyl parathion and p-nitrophenol from a long-term organoposphate pesti- cides of the polluted soil in Hubei Xiantao Pesticide Works. Methyl parathion is a kind of highly toxic organophosphate insecticides and widely used in agriculture to control the pests. The main intermediate product of methyl parathion is p-nitrophenol, a certain kind of aromatic compounds, which is less toxic than methyl parathion itself. Due to its containing of benzene ring structure, its residues may stay for longer time in the environment and lead to a potential threat to the health of human beings as well as that of other animals. The strain allows us to use methyl parathion and p-nitrophenol as the sole carbon and nitrogen source to degrade MP of 500 mg/L and 200 mg/L with its original concentration about 86.8 % and 95.7 % in 24 h, and degrade PNP of 200 mg/L concentration about 92.3%. At the same time, it can also be found that the strain can totally degrade 10 mmol/L NO3 in 15 hours when added to the strain in the denitrification system to enhance its effect. When all the above experiments were done at pH 6 and 30 ℃, the total DNA of the strain can be extracted and amplified by the universal primers of 16S rDNA. After that, the products can be further purified and cloned into the plasmid of pMD18 -T, and sequenced by the universal M13 primers. In case of need, the 16S rDNA sequence can be analyzed by using BLAST software online. And, finally, the software MEGA3.1 can be used to form the phylogenetic tree to identify the 16S rDNA sequence as a Bacillus cereus based on the results of morphologic characteristics, physiological and biochemical properties. In addition, the UV-scanning detector can be used to test if any p-nitrophenol occurs in the whole degradation time because the p-nitrophenol enjoys a special absorptlon peak in the 405nm on the detector. The experimental results of ours show HS-MP12 can degrade MP with

关 键 词：微生物学 甲基对硫磷 对硝基苯酚 生物降解 动态降解 蜡状芽孢杆菌 

分 类 号：X172[环境科学与工程—环境科学]