Modular configurations of living biomaterials incorporating nano-based artificial mediators and synthetic biology to improve bioelectrocatalytic performance: A review

Novel approaches to energize microbial biocatalysts

“…Excited photoelectrons generated by illuminated SNs are highly reductive and readily accepted by membrane-bound proteins (e.g., cytochromes, ferredoxins, hydrogenases, etc.) and electron shuttles (e.g., quinones) to drive specific cell reduction processes and energy generation in microbes (Kornienko et al, 2016;Chen et al, 2022) (Fig. 1).…”

“…Excited photoelectrons generated by illuminated SNs are highly reductive and readily accepted by membrane-bound proteins (e.g., cytochromes, ferredoxins, hydrogenases, etc.) and electron shuttles (e.g., quinones) to drive specific cell reduction processes and energy generation in microbes (Chen et al, 2022;Kornienko et al, 2016) (Figure 1). Hybrid living systems that harvest light energy through SNs can energetically enhance the conversion of inorganic F I G U R E 1 Main challenges on the use of semiconductor nanoparticles (SNs) as energization systems of microbial biocatalysts.…”

“…Excited photoelectrons generated by illuminated SNs are highly reductive and readily accepted by membrane‐bound proteins (e.g., cytochromes, ferredoxins, hydrogenases, etc.) and electron shuttles (e.g., quinones) to drive specific cell reduction processes and energy generation in microbes (Chen et al, 2022 ; Kornienko et al, 2016 ) (Figure 1 ). Hybrid living systems that harvest light energy through SNs can energetically enhance the conversion of inorganic materials, for example, CO 2 , to high value‐added organic chemicals, polymers, fertilizers and energy products (e.g., H 2 ), while they are self‐regenerating, with low waste generation, and operating at an efficiency (product yield based on solar energy input) higher than 80% (Fang et al, 2020 ; Gupta et al, 2021 ; Tremblay et al, 2020 ).…”

“…Thus, it would be worthwhile to explore the possibility to synthesize SNs in bacteria as an alternative/complementary way of cell energization. Synthetic biology approaches to boost electron transfer, for example, modifying conductive cytochromes, intracellular redox mediators, NADH pool, SNs–enzyme nanobiohybrids and so on, will facilitate the tailoring of living hybrid systems to target specific applications (Chen et al, 2022 ; Figure 1 ).…”

Inward-to-outward assembly of amine-functionalized carbon dots and polydopamine to Shewanella oneidensis MR-1 for high-efficiency, microbial-photoreduction of Cr(VI)

“…To improve the overall bioelectrochemical efficiency of biohybrids, modular configurations for all living/nonliving electron transfer machineries must be considered in constructing a reliable hybrid system that integrates a flexible conformational structure with sufficient energetic catalysis efficiency (Chen et al, 2022). Considering the orientation specificity of charge transport (Apetrei et al, 2019), the connections between living and non-living machineries in cell-semiconductor hybrid systems require a stable/efficient interfacial connector to optimize charge transduction similar to natural systems.…”