阿特拉津降解菌CS3的分离鉴定及其降解特性的研究

Isolation, identification, and characterization of atrazine-degrading bacterial strain CS3

为了适应不同环境污染修复需要,分离更多有效的阿特拉津降解菌是十分必要的。鉴于此,本研究从河北省某农药厂排污河中的废水中分离出一株以阿特拉津为唯一氮源生长的高效降解阿特拉津降解菌CS3。经生理生化鉴定和16S rRNA基因序列分析,最终鉴定其为产脲节杆菌(Arthrobacter ureafaciens)。在30℃和pH 7的最适条件下,菌株CS3能在48 h内完全降解50 mg·L^(-1)的阿特拉津,甚至能够在6 d内将500 mg·L^(-1)的阿特拉津完全降解,表明该菌株对阿特拉津具有较好的降解性。菌株CS3含有trzN,atzB,atzC 3个阿特拉津降解基因。菌株CS3具有较宽的温度(10~37℃)和p H(5~11)范围,且具有很好的耐碱性,为未来偏碱环境中阿特拉津污染修复提供了良好的候选菌株。

Isolation of microbial resources from polluted environments used for soil remediation will be increasingly necessary in future agriculture. In view of this, atrazine-degrading bacterial strain CS3, which grows using atrazine as its sole nitrogen source, was isolated from the effluent of a pesticide factory in Hebei Province. Based on its biochemical characterization and 16 S rRNA gene sequence, strain CS3 was identified as Arthrobacter unreafaciences. Its optimum growth temperature and pH were 30 ℃ and 7.0, respectively. Under these conditions,A. unreafaciences CS3 completely degraded 50 mg·L^-1 atrazine within 48 h and 500 mg·L^-1 within 6 days. A. unreafaciences CS3 contains the atrazine-degrading genes trzN, atzB, and atzC and has good growth and atrazine degradation in the pH range 5-11.