Complete uranium bioreduction in 48 hours: Synergistic electron transfer in a synthetic microbial consortium

作者：Xizi Long, Yuanyuan Jiang, Zhaozhong Zhu, Yu Li, Nan Hu, Jun Hong, Hui Wang, Fei Yang · 发表于：Environmental Science and Ecotechnology · 年份：2025 · DOI：10.1016/j.ese.2025.100629 · 被引用次数：3 · 研究领域：Microbial Fuel Cells and Bioremediation、Radioactive element chemistry and processing、Metal Extraction and Bioleaching

Uranium contamination from mining and natural sources poses a major environmental and health risk, as soluble uranium U(VI) readily migrates through groundwater systems. Microbial reduction to insoluble U(IV) via dissimilatory metal-reducing bacteria offers a sustainable remediation method, relying on extracellular electron transfer (EET) to shuttle electrons to extracellular acceptors. Shewanella oneidensis MR-1 ( S .MR-1) serves as a model organism for this process, but its EET efficiency is hindered by limited endogenous redox mediators and biofilm conductivity. Despite advances in genetic engineering, the potential of synthetic microbial communities to enhance EET through interspecies interactions remains underexplored. Here we show a synthetic consortium comprising S .MR-1 and a non-U-reducing isolate, Pseudomonas aeruginosa LXZ1 ( P .LXZ1), that fully reduces U(VI) within 48 hours, compared to only 60% reduction by S .MR-1 alone. This enhancement stems from P .LXZ1-secreted pyocyanin, which binds selectively to S .MR-1's outer-membrane cytochrome OmcA, shifting its redox potential to facilitate directional electron flow along a thermodynamic gradient. Concurrently, conductive extracellular DNA released by P .LXZ1 promotes electron transport and aggregate formation, as evidenced by electrochemical assays, transcriptomics, and molecular dynamics simulations. These synergistic mechanisms alleviate proton-transfer limitations and upregulate metabolic pathways, boosting over...