Light-Driven C4 Biosynthesis from CO2 and H2O via Engineered Photocatalyst-Microbial Consortia.

The development of sustainable technologies for converting CO2 into value-added chemicals using solar energy remains a critical challenge. We presented a biohybrid system integrating Z-scheme photocatalysts with engineered microbial consortia for light-driven succinic acid production from CO2 and H2O without sacrificial agents. The system combined Escherichia coli biofilms expressing formate dehydrogenase for photoelectrochemical CO2 reduction to formate with adaptively evolved Vibrio natriegens for formate upgrading to succinic acid. This configuration achieved 0.06 mM succinic acid in 6 h with an apparent quantum yield of 0.154%. The biofilms maintained conformal contact with photocatalysts through four operational cycles, while V. natriegens viability increased by 11% owing to the formate provided by the biohybrid sheet. Further, isotopic tracing revealed approximately 20% carbon incorporation from CO2. This work establishes a sustainable platform for solar-driven multicarbon synthesis through rational integration of photocatalysis and synthetic microbial consortia.