Shi Xiao-Chen, Wang Kefan, Xue Miao, Mao Weijia, Xu Kai, Tremblay Pier-Luc, Zhang Tian
School of Chemistry, Chemical Engineering, and Life Science, Wuhan University of Technology, Wuhan, 430070, PR China; School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China; Advanced Engineering Technology Research Institute of Zhongshan City, Wuhan University of Technology, Zhongshan, 528437, PR China.
School of Chemistry, Chemical Engineering, and Life Science, Wuhan University of Technology, Wuhan, 430070, PR China.
Chemosphere. 2024 Feb;350:141177. doi: 10.1016/j.chemosphere.2024.141177. Epub 2024 Jan 9.
The fastest-growing microbe Vibrio natriegens is an excellent platform for bioproduction processes. Until now, this marine bacterium has not been examined for bioremediation applications, where the production of substantial amounts of biomass would be beneficial. V. natriegens can perform extracellular electron transfer (EET) to Fe(III) via a single porin-cytochrome circuit conserved in Vibrionaceae. Electroactive microbes capable of EET to Fe(III) usually also reduce toxic metals such as carcinogenic Cr(VI), which is converted to Cr(III), thus decreasing its toxicity and mobility. Here, the performance of V. natriegens was explored for the bioremediation of Cr(VI). At a density of 100 mg/mL, V. natriegens removed 5-20 mg/L Cr(VI) within 30 s and 100 mg/L Cr(VI) within 10 min. In comparison, the model bacterium Escherichia coli grown to a comparable cell density removed Cr(VI) 36 times slower. To eliminate Cr(VI), V. natriegens had to be metabolically active, and functional outer-membrane c-type cytochromes were required. At the end of the Cr(VI) removal process, V. natriegens had reduced all of it into Cr(III) while adsorbing more than half of the metallic ions. These results demonstrate that V. natriegens, with its fast metabolism, is a viable option for the rapid treatment of aqueous pollution with Cr.
生长最快的微生物——嗜盐弧菌是生物生产过程的优良平台。到目前为止，尚未对这种海洋细菌进行生物修复应用方面的研究，而在生物修复应用中大量生物质的产生将是有益的。嗜盐弧菌可通过弧菌科中保守的单个孔蛋白 - 细胞色素回路进行细胞外电子转移（EET）至Fe(III)。能够将EET至Fe(III)的电活性微生物通常也会还原有毒金属，如致癌的Cr(VI)，Cr(VI)会被转化为Cr(III)，从而降低其毒性和迁移性。在此，研究了嗜盐弧菌对Cr(VI)的生物修复性能。在密度为100 mg/mL时，嗜盐弧菌在30秒内去除了5 - 20 mg/L的Cr(VI)，在10分钟内去除了100 mg/L的Cr(VI)。相比之下，生长至可比细胞密度的模式细菌大肠杆菌去除Cr(VI)的速度慢36倍。为了去除Cr(VI)，嗜盐弧菌必须具有代谢活性，并且需要功能性的外膜c型细胞色素。在Cr(VI)去除过程结束时，嗜盐弧菌已将所有Cr(VI)还原为Cr(III)，同时吸附了超过一半的金属离子。这些结果表明，嗜盐弧菌代谢速度快，是快速处理含铬水污染的可行选择。
