Design of Light Driven Hole Bifurcating Proteins

Electron bifurcation reactions divide electrons from two-electron donors into high- and low-energy pools by transporting charge on spatially separated low- and high-potential electron hopping pathways. Bifurcation delivers electrons at potentials that drive downstream reactions in photosynthesis, respiration, and biocatalysis. Recent theoretical studies have described the requirements for effective ground-state electron bifurcation. The aim of this study is to design synthetic bifurcation constructs that can be driven by light. We describe a strategy to bifurcate holes (oxidizing equivalents) efficiently with light, and we present an illustrative energy landscape that could support this design. The design focuses on the electrochemical potentials and distances between cofactors. The analysis finds that hole bifurcation may be driven efficiently with light, guiding the further development of bioinspired networks that bifurcate charge and deliver the charges with prescribed electrochemical potentials.