Cd-induced stress response of Phanerochaete chrysosporium during the biodegradation of BDE-47 was investigated in this study, with the goal of elucidating the tolerance behavior and the detoxification mechanisms of P. chrysosporium to resist the Cd stress in the course of BDE-47 biodegradation, which has implications for expanding the application of P. chrysosporium in the bioremediation of Cd and BDE-47 combined pollution. The results suggested that single BDE-47 exposure did not induce obvious oxidative stress in P. chrysosporium, but coexistent Cd significantly triggered ROS generation, both intracellular ROS level and H₂O₂ content showed positive correlation with Cd concentration. The activities of SOD and CAT were enhanced by low level of Cd (≤ 1 mg/L), but Cd of higher doses (＞1 mg/L) depressed the expression of these two antioxidant enzymes at the later exposure period (3–5 days). The intracellular content of GSH along with GSH/GSSG ratio also exhibited a bell-shaped response with a maximum value at Cd of 1 mg/L. Furthermore, Cd-induced ROS generation resulted in the lipid peroxidation, as indicated by a noticeable increment of MDA content found after 3 days. Moreover, the study also indicated that Cd less than 1 mg/L promoted the production of extracellular protein and quickened the decrease of pH value in the medium, while excessive Cd (＞1 mg/L) would lead to inhibition. These findings obtained demonstrated that P. chrysosporium had a certain degree of tolerance to Cd within a specific concentration range via regulating the antioxidant levels, inducing the synthesis of extracellular protein as well as stimulating the production of organic acids, and 1 mg/L is suggested to be the tolerance threshold of this strains under Cd stress during BDE-47 biodegradation.

本研究以BDE-47生物降解过程中Cd诱导的Phanerochaete chrysosporium的胁迫响应为研究对象，以阐明P. chrysosporium对BDE-47生物降解过程中的抗Cd胁迫的耐受行为和解毒机理。，这对于扩大金孢假单胞菌在Cd和BDE-47复合污染的生物修复中的应用具有重要意义。结果表明，单次接触BDE-47不会在金黄色葡萄球菌中引起明显的氧化应激，但共存的Cd会显着触发ROS的产生，包括细胞内ROS水平和H ₂ O _2。含量与镉浓度呈正相关。低水平的Cd（≤1 mg / L）增强了SOD和CAT的活性，但是较高剂量的Cd（＞ 1 mg / L）则在暴露后期（3-5）抑制了这两种抗氧化酶的表达。天）。GSH的细胞内含量以及GSH / GSSG比也显示出钟形响应，在Cd处的最大值为1 mg / L。此外，Cd诱导的ROS生成导致脂质过氧化，如3天后发现的MDA含量明显增加所表明的。此外，研究还表明，低于1 mg / L的Cd会促进细胞外蛋白质的产生，并加快培养基中pH值的降低，而过量的Cd（> 1 mg / L）会导致抑制作用。获得的这些发现证明金黄色葡萄球菌 通过调节抗氧化剂水平，诱导细胞外蛋白的合成以及刺激有机酸的产生，在特定浓度范围内对镉具有一定程度的耐受性，因此建议该菌株的耐受阈值为1 mg / L在BDE-47生物降解过程中受到Cd胁迫。