Advancing anodic electro-fermentation : insights into energy management, substrate utilizaton, and redox mediation in Pseudomonas putida within a bio-electrochemical system

Abstract

The obligate aerobic nature of Pseudomonas putida limits its biotechnological application, as oxygen supply increases costs and hampers scalability. This thesis explores anodic electro-fermentation in bio-electrochemical systems, where an anode replaces oxygen as terminal electron acceptor. Analyses revealed that glucose uptake pathways are not the main bottleneck; instead, energy limitations and regulatory constraints dominate. Multi-omics data revealed significant metabolic adaptations, including β-oxidation, alternative ATP generation, and the involvement of polyphosphate to compensate for energy limitations. In redox mediator studies, an artificial mediator was directly compared with an endogenous mediator. An evaluation of quinone derivatives highlighted trade-offs between stability and redox potential compatibility. This work provides new insights into P. putida survival under anode-driven, anoxic conditions and advances BES as a sustainable platform for microbial production.