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bioRxiv · 10.1101/2025.08.21.671649

Decoding the Redox-Driven Fate of Organic Micropollutants through Microbial Co-metabolic and ROS-Mediated Degradation in Wastewater

Lyu, B.·Manna, B.·Zhou, X.·Leung, I. K. H.·Singhal, N.
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Abstract

The uncontrolled release of organic micropollutants (OMPs) from wastewater treatment plants highlights a failure to synergize co-metabolic and reactive oxygen species (ROS)-driven biodegradation pathways. Here, we demonstrate that engineered redox cycling--dynamic fluctuations between oxic and anoxic conditions--fundamentally reshapes microbial metabolism and OMP reaction networks to dramatically enhance removal. Using an integrated multi-omics approach centered on paired mass distance (PMD) reactomics, we show that redox cycling increased the removal of 32 diverse OMPs from a baseline of 32% up to 67%. This enhancement was driven by a complete restructuring of degradation mechanisms: cycling stimulated microbial amino acid and fatty acid metabolism by up to 42%, which coupled to controlled ROS production where oxidative pathways (+15.995 Da) accounted for 47% of transformations under intermittent aeration. We mapped distinct "enzymatic fingerprints," with strong correlations (r > 0.7) linking Proteobacteria monooxygenases to oxidative reactions and Rhodobacteraceae dehydrogenases to reductive ones (+2.016 Da), revealing clear functional specialization. Ultimately, the redox regime dictates the entire OMP transformation network topology, shifting pathways from simple hydroxylation to complex, multi-step networks. This work provides a mechanistic framework establishing redox manipulation as a powerful strategy to synergistically activate degradation pathways, allowing existing infrastructure to meet stringent discharge regulations.

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Lyu, B., Manna, B., Zhou, X., Leung, I. K. H., Singhal, N.. 2025-08-25. Decoding the Redox-Driven Fate of Organic Micropollutants through Microbial Co-metabolic and ROS-Mediated Degradation in Wastewater. https://doi.org/10.1101/2025.08.21.671649

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