Project Details
Projekt
Combining stimuli-responsive hydrogels and scaffold-supported microbial biofilms for a self-controlled catalytic activity of a microbial leaf
Subject Area
Biological Process Engineering
Synthesis and Properties of Functional Materials
Synthesis and Properties of Functional Materials
Term
since 2024
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 541298066
In nature, the central mechanism that transforms solar energy into chemical energy is oxygenic photosynthesis. Therefore, microbial (photo)catalysis is envisioned as an efficient and sustainable alternative to current chemical processes. However, attaining high active biomass concentrations and their resilience to environmental conditions such as irradiance and temperature fluctuations constitute major challenges for sustained maintenance of catalytic performance. Our project aims to adopt the nature-based plant leaf concept of self-regulation and sustained maintenance of ist photosynthetic machinery. Using the power of genetically engineered phototrophic biofilms stably grown at high cell density within a porous material scaffold and equipped with a stimuli-responsive hydrogel surface layer at the gas-liquid interface will enable a sustained catalytic process for chemical production. The pH or temperature (T) -responsive hydrogel surface layer will respond to the activity state of the microbial consortia within the porous scaffold and allow self-control of ist catalytic performance by gas permeation control, similar to the principle of plant leaf surfaces. Thus, the microbial leaf concept will be accomplished based on our expertise in utilizing microbial consortia (e.g. Synechocystis, Pseudomonas) for chemical production, as well as engineering of material scaffolds, including synthesis of pH- and T-responsive hydrogels for developing the self-controlled activity of a living catalytic material (LCM). In our case study, we will investigate the performance of microbial biofilms within porous polymer scaffolds for the catalytic transformation of cyclohexane to ɛ-caprolactone or adipic acid as precursors for industrial polymer synthesis. Low- vs high-light conditions, similar to the day-night cycle, will be shown to trigger microenvironmental conditions within the LCM, leading to swollen and collapsed states of the pH-responsive hydrogel layer. The responsive hydrogel layer will be synthesized by electron beam-initiated polymerization of N-isopropylamide and acrylic acid monomers with adjustment of the phase transition range. The different swelling states and physicochemical characteristics of the hydrogel layer, triggered by the microbial cell's activity, will control the influx of cyclohexane for the catalytic reaction of the adaptive LCM, enabling optimal performance at different light conditions. In the future, our new knowledge should exploit the potential of the microbial leaf concept and allow self-sustained biotechnological processes with a broad application range.
DFG Programme
Priority Programmes
