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

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 cyclingdynamic 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.