Visible light-driven, external mediator-free H2 production by a combination of a photosensitizer and a whole-cell biocatalyst: Escherichia coli expressing [FeFe]-hydrogenase and maturase genes

Abstract

Visible light-driven H₂ production contributes to an efficient solar energy conversion. Here, we demonstrate a visible light-driven, mediator-free H₂ production system by coupling a photosensitizer and a genetically engineered whole-cell biocatalyst: Escherichia coli expressing clostridial [FeFe]-hydrogenase and maturase genes. The system consists of three components: a photosensitizer, eosin Y; an electron donor, triethanolamine; and the E. coli whole-cell biocatalyst. Under light irradiation, the whole-cell-based system formed H₂ without an additional electron mediator and achieved a high apparent quantum yield at 530 nm (over 10%). This whole-cell-based system provides simple, efficient, and clean H₂ production.