Diep Patrick, Leo Shen Heping, Wiesner Julian A, Mykytczuk Nadia, Papangelakis Vladimiros, Yakunin Alexander F, Mahadevan Radhakrishnan
BioZone - Centre for Applied Bioscience and Bioengineering, Department of Chemical Engineering and Applied Chemistry University of Toronto Toronto Canada.
MIRARCO Mining Innovation Laurentian University Sudbury Canada.
Eng Life Sci. 2023 May 24;23(7):2200133. doi: 10.1002/elsc.202200133. eCollection 2023 Jul.
Mine wastewater often contains dissolved metals at concentrations too low to be economically extracted by existing technologies, yet too high for environmental discharge. The most common treatment is chemical precipitation of the dissolved metals using limestone and subsequent disposal of the sludge in tailing impoundments. While it is a cost-effective solution to meet regulatory standards, it represents a lost opportunity. In this study, we engineered to overexpress its native NikABCDE transporter and a heterologous metallothionein to capture nickel at concentrations in local effluent streams. We found the engineered strain had a 7-fold improvement in the bioaccumulation performance for nickel compared to controls, but also observed a drastic decrease in cell viability due to metabolic burden or inducer (IPTG) toxicity. Growth kinetic analysis revealed the IPTG concentrations used based on past studies lead to growth inhibition, thus delineating future avenues for optimization of the engineered strain and its growth conditions to perform in more complex environments.
矿山废水通常含有溶解态金属，其浓度低到无法用现有技术进行经济提取，但又高到无法环境排放。最常见的处理方法是使用石灰石对溶解态金属进行化学沉淀，随后将污泥处置在尾矿库中。虽然这是满足监管标准的一种经济有效的解决方案，但却意味着机会的丧失。在本研究中，我们对[具体内容未提及]进行工程改造，使其过表达其天然的NikABCDE转运蛋白和一种异源金属硫蛋白，以捕获当地废水流中一定浓度的镍。我们发现，与对照相比，工程菌株对镍的生物积累性能提高了7倍，但也观察到由于代谢负担或诱导剂（IPTG）毒性导致细胞活力急剧下降。生长动力学分析表明，基于以往研究使用的IPTG浓度会导致生长抑制，从而为优化工程菌株及其生长条件以在更复杂环境中发挥作用指明了未来的优化方向。
