Institute of Pesticide and Environmental Toxicology, Hangzhou, 310058, China; Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Hangzhou, 310058, China; Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.
Institute of Pesticide and Environmental Toxicology, Hangzhou, 310058, China; Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Hangzhou, 310058, China.
Chemosphere. 2021 Feb;264(Pt 2):128514. doi: 10.1016/j.chemosphere.2020.128514. Epub 2020 Oct 4.
Residual injury of atrazine to the succeeding crops has been frequently reported. It is necessary to find a solution for the detoxification of atrazine contaminated soil. A high-efficient bacterial strain Arthrobacter sp. C2 for atrazine degradation was isolated in this study. The genomic information of the isolate C2, and its degradation characteristics and potential application in detoxification of atrazine contaminated soil were investigated. The results indicated that the isolate C2 genome contained 4,305,216 bp nucleotides, three plasmids, and 4705 coding genes. The degradation rates of atrazine at levels of 1, 10, 100 mg/L by the isolate C2 were 0.34, 1.94, 18.64 mg/L/d, respectively. The optimum temperature and pH for the isolate C2 to degrade atrazine were 30 °C and 7.0-9.0. Based on the metabolites detected by UPLC-TOF-MS/MS and genome annotation of the isolate C2, a common metabolic pathway of atrazine was proposed as that atrazine is firstly dechlorinated into hydroxyatrazine, and subsequently to N-isopropylammelide via dealkylation, and ultimately deaminated to cyanuric acid. Introduction of the isolate C2 into soil can enhance degradation of atrazine and thus eliminate the toxic effect of this herbicide on wheat growth. Our results indicate that the strain C2 could be a potential bioresource for bioremediation of atrazine contaminated soil.
莠去津对后续作物的残留危害屡有报道。因此，有必要寻找一种莠去津污染土壤的解毒方法。本研究从土壤中筛选到一株高效莠去津降解菌节杆菌（Arthrobacter sp.）C2。对该菌的基因组信息、降解特性及其在莠去津污染土壤修复中的应用潜力进行了研究。结果表明，C2 基因组大小为 4,305,216 bp，含有 3 个质粒和 4705 个编码基因。C2 菌对 1、10、100 mg/L 莠去津的降解速率分别为 0.34、1.94、18.64 mg/L/d。该菌降解莠去津的最适温度和 pH 值分别为 30℃和 7.0-9.0。根据 UPLC-TOF-MS/MS 检测到的代谢产物和 C2 基因组注释，提出了莠去津的可能代谢途径，即莠去津首先脱氯生成羟基莠去津，然后脱烷基化生成异丙基脒，最后脱氨生成三聚氰胺。将 C2 菌引入土壤中可以增强莠去津的降解，从而消除莠去津对小麦生长的毒害作用。本研究结果表明，C2 菌株可作为一种潜在的生物资源，用于修复莠去津污染土壤。
