阿特拉津降解菌Acinetobacter sp.DNS32对无机氮源的响应  

Response of an atrazine-degrading bacterium strain Acinetobacter sp. DNS32 to inorganic nitrogen source

作　　者：王志刚[1,2] 张颖[2] 郭火生[2] 伊欢[1] 

机构地区：[1]齐齐哈尔大学生命科学与农林学院,黑龙江齐齐哈尔161006 [2]东北农业大学资源与环境学院,黑龙江哈尔滨150030

出　　处：《微生物学通报》2014年第8期1541-1546,共6页Microbiology China

基　　金：黑龙江省高校长江学者后备支持计划项目(No.2012CJHB001;CSCP);黑龙江省高校创新团队建设计划项目(No.2013TD003)

摘　　要：【目的】研究Acinetobacter sp.DNS32的生长、阿特拉津降解能力和降解基因转录水平的表达对无机氮素的响应关系,为菌株的工程应用提供指导与理论基础。【方法】以Acinetobactersp.DNS32为对象,采用摇瓶法研究菌株在阿特拉津培养基中菌株生长情况及降解能力对外加硝态氮与铵态氮的响应关系,利用荧光定量PCR技术检测DNS32降解基因表达量对外加无机氮源的响应关系。【结果】外加无机氮源可以促进DNS32菌株的生长,提高阿特拉津降解能力,无机氮源对DNS32菌株的trzN、atzB和atzC 3种降解基因表达均有促进作用,加入无机氮源的试验处理中DNS32菌株trzN基因的表达量最高可达对照的11.252±2.408倍,推断DNS32菌株的这3种降解基因所编码的酶是稳定表达的组成酶。【结论】DNS32降解阿特拉津不受"氮饥饿"诱导机制调控,且无机氮源的存在对菌株的生长与降解有促进作用,因此菌株在土壤修复实践中具有广阔的应用前景。[Objective] The objective was to study the response relationship between the growth, degradation ability and gene expression of Acinetobacter sp. DNS32 and inorganic nitrogen source, and to provide guidance and theoretical foundation for engineering application of strain DNS32. [Methods] Taked Acinetobacter sp. DNS32 for research object, the effect of inorganic nitrogen source were studied on the growth and degradation ability of strain DNS32 by the bottle shaking method, and the influence of inorganic nitrogen on the expression of the degrading genes was studied by RT-qPCR. [Results] The results showed that the inorganic nitrogen in culture medium could promote the growth and the ability to degrade atrazine of DNS32 strain. The inorganic nitrogen could increase the expression of the trzN, atzB and atzC. Compared with the control treatment, the expression of trzN gene in the treatments with inorganic nitrogen could be 11.25＋2.40-folds. It was inferred that the atrazine-degrading enzyme coded by the three degrading genes may be constitutively in strain DNS32. [Conclusion] The degradation of atrazine in the strain DNS32 is not controlled by the induction mechanism of ＂nitrogen starvation＂. The inorganic nitrogen can promote growth and degradation ability of strain DNS32. Therefore, strain DNS32 has broad application prospects in soil remediation practice.

关 键 词：阿特拉津 ACINETOBACTER SP DNS32 无机氮源 降解能力 基因表达 

分 类 号：X172[环境科学与工程—环境科学] X592