Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
J Hazard Mater. 2022 Feb 15;424(Pt C):127538. doi: 10.1016/j.jhazmat.2021.127538. Epub 2021 Oct 20.
It is of great interest to explore physiological metabolism of electrochemically active bacteria (EAB) for combined organics and heavy metals in single-chamber microbial electrolysis cells (MECs). Four pure culture EAB varying degrees responded to the combined acetate (1.0-5.0 g/L) and Cd(II) (20-150 mg/L) at different initial concentrations in the single-chamber MECs, shown as significant relevance of Cd(II) removal (2.57-7.35 mg/L/h) and H production (0-0.0011 m/m/h) instead of acetate removal (73-130 mg/L/h), to these EAB species at initial Cd(II) below 120 mg/L and initial acetate below 3.0 g/L. A high initial acetate (5.0 g/L) compensated the Cd(II) inhibition and broadened the removal of Cd(II) to 150 mg/L. These EAB physiologically released variable amounts of extracellular polymeric substances with a compositional diversity in response to the changes of initial Cd(II) and circuital current whereas the activities of typical intracellular enzymes were more apparently altered by the initial Cd(II) than the circuital current. These results provide experimental validation of the presence, the metabolic plasticity and the physiological response of these EAB directed by the changes of initial Cd(II) and acetate concentrations in the single-chamber MECs, deepening our understanding of EAB physiological coping strategies in metallurgical microbial electro-ecological cycles.
探索电化学活性细菌（EAB）在单室微生物电解池（MEC）中对有机和重金属的生理代谢对于冶金微生物电化学循环中 EAB 的生理应对策略的理解具有重要意义。四种不同程度的纯培养 EAB 对单室 MEC 中不同初始浓度的组合乙酸盐（1.0-5.0 g/L）和 Cd(II)（20-150 mg/L）表现出显著的相关性，即 Cd(II)去除（2.57-7.35 mg/L/h）和 H 生成（0-0.0011 m/m/h）而不是乙酸盐去除（73-130 mg/L/h），这与这些 EAB 物种在初始 Cd(II)低于 120 mg/L 和初始乙酸盐低于 3.0 g/L 时的情况有关。高初始乙酸盐（5.0 g/L）补偿了 Cd(II)的抑制作用，并拓宽了 Cd(II)的去除范围至 150 mg/L。这些 EAB 会根据初始 Cd(II)和电路电流的变化，生理上释放出不同量的细胞外聚合物物质，其组成多样性也会发生变化，而典型的细胞内酶的活性则更多地受到初始 Cd(II)的影响，而不是电路电流的影响。这些结果为这些 EAB 在单室 MEC 中受初始 Cd(II)和乙酸盐浓度变化的存在、代谢可塑性和生理反应提供了实验验证，深化了我们对冶金微生物电化学生态循环中 EAB 生理应对策略的理解。
