甲基对硫磷降解菌DLL-1的分离、鉴定及降解性研究

从长期施用甲基对硫磷的污染土壤中分离到一株能以甲基对硫磷为唯一碳源生长且能将其完全矿化的细菌 Ｄ Ｌ Ｌ－ １ ，经鉴定，为邻单胞菌（ Ｐｌｅｓｉｏｍｏｎａｓ ｓｐ ．） ．该菌株３ ｈ 内对５０ ｍｇ／ Ｌ甲基对硫磷的降解率为９３ ％ ，２４ｈ 内对５０ ｍｇ／ Ｌ甲基对硫磷的降解率为９５ ％ 以上．在葡萄糖铵盐培养基中， Ｄ Ｌ Ｌ１ 对甲基对硫磷的耐受浓度和降解速度均增大．降解曲线表明延滞期内，菌体依靠上一生长阶段分泌的酶类对甲基对硫磷进行降解，一旦菌体开始生长，则检测不到中间代谢产物对硝基苯酚的存在．生长情况和粗酶液试验均显示 Ｄ Ｌ１ 优良的降解性状

ISOLATION,IDENTIFICATION AND CHARACTERS OF METHYL PARATHION DEGRADING BACTERIUM

One methyl parathion degrading bacterium was isolated from contaminated soil where methyl parathion had been used for a long time. It degrade methyl parathion used it as sole carbon source. The bacterium was identified as Plesiomonas sp. and named DLL 1.The removal rate of was 93% in 3 hours and more than 95% in 24 h respectively. In the glucose media, the enduring and degrading ability of DLL 1 to methyl parathion became stronger. The growth and degradation curve showed that the decontamination of methyl parathion in the lag period was attributed to the enzyme produced in the last growth period, and p Nitrophenol can not be found once DLL 1 began to grow. The hard degradation of methyl parathion was verified by feathers of DLL 1's growth and raw enzyme.