3, 5, 6-Trichloro-2-pyridinol (TCP) is a metabolite of the insecticide chlorpyrifos and the herbicide triclopyr, and it is higher toxic than the parent compounds. Microbially-mediated mineralization appears to be the primary degradative pathway and the important biological process of detoxification. However, little information is available on TCP complete metabolic pathways and mechanisms. In this study, the degradation of TCP was studied with a novel strain Micrococcus luteus ML isolated from a stable TCP degrading microbiota. Strain ML was capable of degrading 61.6% of TCP (50 mg/L) and 35.4% of chlorpyrifos (50 mg/L) at 24 h and 48 h under the optimal conditions (temperature: 35 °C; pH: 7.0), respectively. It could also degrade 3, 5-dichloro-2-pyridone, 6-chloropyridin-2-ol, 2-hydroxypyridine and phoxim when provided as sole carbon and energy sources. Seven TCP intermediate metabolites were detected in strain ML and two possible degradation pathways of TCP were proposed on the basis of LC–MS analysis. Both the hydrolytic-oxidative dechlorination pathway and the denitrification pathway might be involved in TCP biodegradation by strain ML. To the best of our knowledge, this is the first report on two different pathways responsible for TCP degradation in one strain, and this finding also provides novel information for studying the metabolic mechanism of TCP in pure culture.

3, 5, 6-Trichloro-2-pyridinol (TCP) 是杀虫剂毒死蜱和除草剂绿草定的代谢产物，毒性高于母体化合物。微生物介导的矿化似乎是主要的降解途径和重要的解毒生物学过程。然而，关于 TCP 完整代谢途径和机制的信息很少。在这项研究中，使用一种新菌株藤黄微球菌研究了 TCP 的降解从稳定的 TCP 降解微生物群中分离出的 ML。在最佳条件（温度：35 °C；pH：7.0）下，菌株 ML 在 24 小时和 48 小时分别能够降解 61.6% 的 TCP（50 mg/L）和 35.4% 的毒死蜱（50 mg/L） . 当作为唯一的碳源和能源提供时，它还可以降解 3, 5-二氯-2-吡啶酮、6-氯吡啶-2-醇、2-羟基吡啶和辛硫磷。在菌株 ML 中检测到 7 种 TCP 中间代谢物，并在 LC-MS 分析的基础上提出了 TCP 的两种可能降解途径。水解-氧化脱氯途径和反硝化途径都可能参与菌株 ML 对 TCP 的生物降解。据我们所知，这是第一份关于导致同一菌株中 TCP 降解的两种不同途径的报告，