Effect of metal accumulation-associated oxidative stress on the combined toxicity of quantum dots with Cu(2+) to Bacillus subtilis.
Effect of metal accumulation-associated oxidative stress on the combined toxicity of quantum dots with Cu(2+) to Bacillus subtilis.
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DOI：
10.1016/j.etap.2016.03.013
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发表时间：
2016-06
影响因子：
4.3
通讯作者：
Jianhua Zhao;Yuxia Zhao;Bo Liu;Ken Zhong;Hejin Yao;Kuangfei Lin
中科院分区：
文献类型：
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作者：
Jianhua Zhao;Yuxia Zhao;Bo Liu;Ken Zhong;Hejin Yao;Kuangfei Lin
量子点（QD）纳米粒子可与土壤中的Cu 2+共存，并能吸附进入细菌细胞的Cu 2+，从而促进细胞铜积累，增强这两种化学物质的联合毒性。对枯草芽孢杆菌的毒性试验结果表明，在安全浓度（低于IC 50值）下添加MPA-CdTe量子点，对枯草芽孢杆菌的毒性更高，细胞活力降低约2倍，细胞内铜含量增加。ROS水平也增加了约500%，SOD活性改变后，QD添加。单独Cu ~（2+）处理降低了B.枯草杆菌的比例为8%-35%。这一发现不受QD添加的影响。此外，增加细胞铜浓度作为结果QD除了增强毒性，主要是通过产生超氧阴离子。然而，这种现象并没有中断土壤微生物的物理-生物反应。
Quantum dot (QD) nanoparticles can coexist with Cu2+in soil and can adsorb Cu2+entering into bacterial cells, thereby promoting cellular copper accumulation and enhancing the combined toxicity of these two chemicals. Toxicity test results onBacillus subtilisshowed that the addition of safe concentrations of MPA-CdTe QDs to Cu2+culture (levels under IC50value) resulted in higher toxicity with about twofold reduction in cell viability and increased intracellular Cu content. ROS levels also increased by about 500%, and SOD activity was altered after QD addition. Treatment with Cu2+alone decreased the α-amylase activity ofB. subtilisby 8%–35%. This finding was not affected by QD addition. Moreover, increased cellular copper concentration as a result of QD addition enhanced toxicity primarily by producing superoxide anions. However, this phenomenon did not interrupt the physical–biological responses of soil microbes.