Pyraclostrobin, a widely used fungicide, poses significant risks to both the environment and human health. However, research on the microbial degradation process of pyraclostrobin was scarce. Here, a pyraclostrobin-degrading strain, identified as sp. Pyr-1, was isolated from activated sludge. Pyraclostrobin was efficiently degraded by strain Pyr-1, and completely eliminated within 6 d in the presence of glucose. Additionally, pyraclostrobin degradation was significantly enhanced by the addition of divalent metal cations (Mn and Cu). The degradation pathway involving ether bond and bond cleavage was proposed by metabolite identification. The sodium alginate-immobilized strain Pyr-1 had a higher pyraclostrobin removal rate from contaminated lake water than the free cells. Moreover, the toxicity evaluation demonstrated that the metabolite 1-(4-chlorophenyl)-1H-pyrazol-3-ol significantly more effectively inhibited than pyraclostrobin, while its degradation products by strain Pyr-1 alleviated the growth inhibition of which confirmed that the low-toxic metabolites were generated from pyraclostrobin by strain Pyr-1. The study provides a potential strain Pyr-1 for the bioremediation in pyraclostrobin-contaminated aquatic environments.

中文翻译：

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伯克霍尔德杆菌对甲氧基丙烯酸酯类杀菌剂唑菌胺酯的生物降解。 Pyr-1：特征、降解途径、水体修复和毒性评估

唑菌胺酯是一种广泛使用的杀菌剂，对环境和人类健康构成重大风险。然而，目前对唑菌胺酯微生物降解过程的研究还很少。在这里，一种唑菌胺酯降解菌株，被鉴定为 sp。 Pyr-1，是从活性污泥中分离出来的。吡唑醚菌酯被菌株 Pyr-1 有效降解，并在葡萄糖存在下 6 d 内完全消除。此外，添加二价金属阳离子（Mn 和 Cu）显着增强了唑菌胺酯的降解。通过代谢物鉴定提出了涉及醚键和键断裂的降解途径。海藻酸钠固定化菌株 Pyr-1 对受污染湖水的唑菌胺酯去除率高于游离细胞。此外，毒性评价表明，代谢物1-(4-氯苯基)-1H-pyrazol-3-ol的抑制效果显着高于唑菌胺酯，而菌株Pyr-1的降解产物减轻了其生长抑制，这证实了低浓度-菌株Pyr-1从唑菌胺酯产生有毒代谢物。该研究为唑菌胺酯污染的水生环境中的生物修复提供了潜在的菌株 Pyr-1。