2,4-滴丁酯降解菌Enterobacter sp.M11-3的分离和鉴定

Isolation and Identification of 2,4-D Butyl Ester-degrading Bacterium of Enterobacter sp.M11-3

【目的】利用生物降解修复2，4-滴丁酯污染的土壤。【方法】使用以2，4-滴丁酯为唯一碳源和能源的无机盐培养基对菌株培养，利用高效液相色谱法测定农药降解率，分离筛选2，4-滴丁酯高效降解菌。通过形态学观察及16SrRNA序列分析进行菌种鉴定，测定菌株的最佳生长条件和对其他11种农药的降解率。【结果】分离得到的菌株M11-3对2，4-滴丁酯的降解率为99．98％，初步鉴定为肠杆菌属（Enterobacter sp．）。确定了该菌株最佳的生长温度为25℃、pH值为7．0，对毒死蜱和螺螨酯的降解率为37．25％～54．34％，对莠去津、吡虫啉、乙嘧酚磺酸酯、氟铃脲、啶虫脒和氯氰菊酯的降解率为15．53％～28．77％。【结论】菌株M11-3可为2，4-滴丁酯污染土壤的生物修复提供适宜的菌种资源。

[Aims] In order to renovate 2,4-D butyl ester-contaminated soil through biodegradation. [Methods] A high-effective 2,4-D butyl ester-degrading bacterium was isolated by culturing in mineral salt medium with 2,4-D butyl ester as sole carbon and energy source. In addition, the degradation rates of the pesticides were detected by HPLC. The identification of strain was studied based on morphology and 16S rRNA gene sequence analysis, the best cultivating conditions and the degradation rates of other 11 pesticides were also determined. [Results] The degradation rate of 2,4-D butyl ester by the isolated strain M11-3 was 99.98%, and the strain was identified as Enterobacter sp. The best cultivating temperature and pH of the strain were 25 ~C and 7.0, respectively. The degradation rates of chlorpyrifos and spirodiclofen by the strain were 37.25-54.34%, the degradation rates of atrazine, imidacloprid, bupirimate, hexaflumuron, acetamiprid and cypermethrin were 15.53-28.77%. [Conclusions] The strain Mll-3 is a suitable candidate in bioremediation of 2,4-D butyl ester-contaminated soil.