College of Science, China Agricultural University, Beijing 100083, PR China.
College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China.
Ecotoxicol Environ Saf. 2018 Aug 15;157:111-120. doi: 10.1016/j.ecoenv.2018.03.074. Epub 2018 Mar 31.
Chlorimuron-ethyl is a typical long-term residual sulfonylurea herbicide whose long period of residence poses a serious hazard to rotational crops. Microbial degradation is considered to be the most acceptable method for its removal, but the degradation mechanism is not clear. In this work, we investigated gene expression changes during the degradation of chlorimuron-ethyl by an effective chlorimuron-ethyl-degrading bacterium, Rhodococcus erythropolis D310-1. The genes that correspond to this degradation and their mode of action were identified using RNA-Seq and qRT-PCR. The RNA-Seq results revealed that 500 genes were up-regulated during chlorimuron-ethyl degradation by strain D310-1. KEGG annotation showed that the dominant metabolic pathways were "Toluene degradation" and "Aminobenzoate degradation". Combining GO and KEGG classification with the relevant literature, we predicted that cytochrome P-450, carboxylesterase, and monooxygenase were involved in metabolic chlorimuron-ethyl biodegradation and that the enzyme active site and mode of action coincided with the degradation pathway proposed in our previous study. qRT-PCR experiments suggested that the R. erythropolis D310-1 carboxylesterase, cytochrome P-450 and glycosyltransferase genes were the key genes expressed during chlorimuron-ethyl biodegradation. To the best of our knowledge, this report is the first to describe the transcriptome analysis of a Rhodococcus species during the degradation of chlorimuron-ethyl.
氯嘧磺隆乙是一种典型的长残留磺酰脲类除草剂，其长残留期对轮作作物构成严重危害。微生物降解被认为是去除它的最可接受的方法，但降解机制尚不清楚。在这项工作中，我们研究了有效降解氯嘧磺隆乙的红球菌 D310-1 降解氯嘧磺隆乙过程中的基因表达变化。使用 RNA-Seq 和 qRT-PCR 鉴定了与该降解相关的基因及其作用方式。RNA-Seq 结果表明，菌株 D310-1 降解氯嘧磺隆乙时，有 500 个基因上调。KEGG 注释表明，主要代谢途径是“甲苯降解”和“邻氨基苯甲酸降解”。将 GO 和 KEGG 分类与相关文献相结合，我们预测细胞色素 P-450、羧酸酯酶和单加氧酶参与代谢氯嘧磺隆乙的生物降解，酶的活性位点和作用方式与我们之前研究提出的降解途径一致。qRT-PCR 实验表明，红球菌 D310-1 的羧酸酯酶、细胞色素 P-450 和糖基转移酶基因是氯嘧磺隆乙生物降解过程中关键表达的基因。据我们所知，这是首次描述在氯嘧磺隆乙降解过程中罗德里格斯菌属的转录组分析。
