School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, People's Republic of China.
School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, People's Republic of China.
Sci Total Environ. 2020 Dec 15;748:141174. doi: 10.1016/j.scitotenv.2020.141174. Epub 2020 Jul 25.
Antimony (Sb) pollution poses a severe health threat to ecosystems. However, the toxic effects of Sb on biota are far from being elucidated. One of the unresolved questions is the molecular signal pathways underlying microbial adaptation to excess antimonite or Sb(III) exposure. The response of a Sb(III)-resistant bacterium Acinetobacter. johnsonii JH7 to Sb(III) stress was investigated using genomic and proteomic profiling. Sb(III) induced the formation of reactive oxygen species thereby leading to oxidative stress and the up-regulation of antioxidant enzyme activities. In addition, two important operons (ars and pst) playing critical roles in this cellular response were identified. The ars proteins functioned cooperatively to expel Sb(III) thereby decreasing antimonite toxicity. Downregulation of the phosphate-specific transporter might reduce the uptake of Sb(V) while hindering phosphorus assimilation. Interaction of Sb(III) with JH7 strain cells also affected peptide syntheses and folding, energy conversion, and stability of the cellular envelope. The present study provides for the first time a global map of cellular adaptation to excess Sb(III). Such information is potentially useful to future Sb pollution remediation strategies.
锑 (Sb) 污染对生态系统构成了严重的健康威胁。然而，Sb 对生物群的毒性影响还远未阐明。一个悬而未决的问题是微生物适应过量亚锑酸盐或 Sb(III)暴露的分子信号通路。使用基因组和蛋白质组谱分析研究了耐 Sb(III)细菌不动杆菌 JH7 对 Sb(III)胁迫的反应。Sb(III)诱导活性氧的形成，从而导致氧化应激和抗氧化酶活性的上调。此外，还确定了两个在细胞反应中起关键作用的重要操纵子（ars 和 pst）。ars 蛋白协同作用将 Sb(III)排出，从而降低亚锑酸盐毒性。磷酸盐特异性转运蛋白的下调可能会减少 Sb(V)的摄取，同时阻碍磷的同化。Sb(III)与 JH7 菌株细胞的相互作用还影响肽的合成和折叠、能量转换以及细胞包膜的稳定性。本研究首次提供了 Sb(III)过量适应的细胞的全局图谱。这些信息对于未来的 Sb 污染修复策略可能是有用的。
