一株阿特拉津降解菌株L-1的鉴定和降解特性研究

目的]鉴定1株阿特拉津(ATZ)降解菌株,并对其降解特性进行研究。方法]通过对取自城市污水处理厂的污泥进行驯化培养,分离能够降解除草剂ATZ的菌株;通过16S rDNA基因序列分析及生理生化试验对菌株进行鉴定,并对其室内降解效果进行优化。结果]试验分离到1株能降解ATZ的菌株L-1,该菌株与Arthrobacter菌株基因相似,同源性达99%以上,结合生理生化方法,确定该菌株为节杆菌(Arthrobacter sp.);L-1降解ATZ时培养基的最佳碳源为葡萄糖,最佳加入量为3 g/L。在此条件下,将L-1接种于阿特拉津无机盐培养基(ATZ浓度为500 mg/L)96 h后降解率达94.8%。结论]该研究为进一步研究ATZ降解菌株及其在ATZ微污染水体生物修复中的应用奠定了基础。

Study on Identification and Degradation Characteristics of An Atrazine-degrading Strain L-1

Objective] The paper was to identify an atrazine-degrading strain and study its degradation characteristics. Method ] Atrazine-de- grading strains were isolated by sludge culture of Municipal sewage treatment plant. The strains were identified by the analysis of physiological and biochemical tests and 16S rDNA gene sequence,and the indoor degradation effects were optimized. Result] An atrazine-degrading strain L-1 was isolated. The gene of L-1 and Arthrobacter strain were similar with homology more than 99% ,and combining with physiological and biochemical methods ,the strain was identified as Arthrobacter sp. The best carbon source of the atrazine degradation medium was glucose ,and the best adding amount was 3 g/L. Under these conditions ,the degradation rate was up to 94.8% 96 h after the L-1 inoculated in atrazine inorganic salts medium （atrazine concentration for 500 mg/L）. Conclusion] The study laid a foundation for the further study of atrazine-degrading strains and the appli- cation in the bioremediation of ATZ polluted water.