Designer photosynthetic organisms for photobiological production of ethanol from carbon dioxide and water

Abstract

This chapter describes an invention on photosynthetic ethanol production through application of synthetic biology. The designer plants, designer algae, and designer plant cells are created such that the endogenous photosynthesis regulation mechanism is tamed, and the reducing power (NADPH) and energy (ATP) acquired from the photosynthetic water splitting and proton gradient-coupled electron transport process are used for immediate synthesis of ethanol (CH3CH2OH) directly from carbon dioxide (CO2) and water (H2O). This photobiological ethanol-production method eliminates the problem of recalcitrant lignocellulosics by bypassing the bottleneck problem of the conventional biomass technology. The photosynthetic ethanol-production technology is expected to have a much higher solar-to-ethanol energy-conversion efficiency than the conventional technology. Furthermore, this approach enables the use of seawater for photobiological production of ethanol without requiring freshwater or agricultural soil, since the designer photosynthetic organisms can be created from certain marine algae that can use seawater.