State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
J Hazard Mater. 2023 Feb 5;443(Pt B):130245. doi: 10.1016/j.jhazmat.2022.130245. Epub 2022 Oct 22.
Bioleaching is intensively investigated for recovering valuable metals such as Li, Co, Ni and Cu. Nickel ion stress threatens the health of microorganisms when Ni starts to accumulate in the leachate during the bioleaching of materials that are rich in Ni, such as spent lithium-ion batteries. The possible mechanisms underlying the response of S. thermosulfidooxidans to nickel ion stress were analyzed using a multi-scale approach. Under the condition of nickel ion stress, high concentrations of nickel ions were immobilized by extracellular polymeric substances, while concentrations of nickel ions inside the cells remained low. The intracellular adenosine triphosphate (ATP) concentration and H-ATPase activity increased to maintain normal cell growth and metabolic activities. Scavenging abilities of S. thermosulfidooxidans for hydrogen peroxide and superoxide anion were enhanced to reduce oxidative damage induced by nickel ion stress. There were 734 differentially expressed genes identified by RNA-seq under nickel ion stress. Most of them were involved in oxidative phosphorylation, glutathione metabolism and genetic information processing, responsible for intracellular energy utilization, intracellular antioxidant capacity and DNA damage repair, respectively. The results of this study are of major significance for in-depth understanding of the mechanisms of acidophilic microorganisms' resistance to metal ions.
生物浸出技术被广泛用于回收有价金属，如 Li、Co、Ni 和 Cu。当富含 Ni 的材料（如废弃锂离子电池）在生物浸出过程中浸出液中开始积累 Ni 时，镍离子胁迫会威胁微生物的健康。本研究采用多尺度方法分析了嗜酸硫杆菌应对镍离子胁迫的可能机制。在镍离子胁迫下，细胞外聚合物将高浓度的镍离子固定，而细胞内的镍离子浓度保持较低水平。细胞内三磷酸腺苷 (ATP) 浓度和 H+-ATP 酶活性增加，以维持正常的细胞生长和代谢活动。嗜酸硫杆菌对过氧化氢和超氧阴离子的清除能力增强，以减少镍离子胁迫诱导的氧化损伤。镍离子胁迫下通过 RNA-seq 鉴定出 734 个差异表达基因。它们大多数参与氧化磷酸化、谷胱甘肽代谢和遗传信息处理，分别负责细胞内能量利用、细胞内抗氧化能力和 DNA 损伤修复。本研究结果对深入了解嗜酸微生物对金属离子的抗性机制具有重要意义。
