Reversing Electron Transfer Chain for Light-Driven Hydrogen Production in Biotic-Abiotic Hybrid Systems

The biotic-abiotic photosynthetic system integratinginorganic light absorbers with whole-cell biocatalysts innovates theway for sustainable solar-driven chemical transformation. Funda-mentally, the electron transfer at the biotic-abiotic interface, whichmay induce biological response to photoexcited electron stimuli,plays an essential role in solar energy conversion. Herein, weselected an electro-active bacteriumShewanella oneidensisMR-1 as amodel, which constitutes a hybrid photosynthetic system with a self-assembled CdS semiconductor, to demonstrate unique biotic-abiotic interfacial behavior. The photoexcited electrons from CdSnanoparticles can reverse the extracellular electron transfer (EET)chain withinS. oneidensisMR-1, realizing the activation of a bacterialcatalytic network with light illumination. As compared with bareS.oneidensisMR-1, a significant upregulation of hydrogen yield (711-fold), ATP, and reducing equivalent (NADH/NAD+) was achieved in theS. oneidensisMR-1-CdS under visible light. This worksheds light on the fundamental mechanism and provides design guidelines for biotic-abiotic photosynthetic systems.

Automated summary

The biotic-abiotic photosynthetic system combines inorganic light absorbers with whole-cell biocatalysts, utilizing photoexcited electrons to activate bacterial catalytic networks for sustainable solar-driven chemical transformations.