Yeast single-cell proteins from CO2 with tandem biological systems.

Production of customized yeast single-cell protein (SCP) from CO2 offers a sustainable avenue to convert a major carbon emission process into a carbon-conserving production route of food and feed. Here, we highlight a specific approach for SCP production from CO2 using sequentially connected yet spatially separated tandem biological systems, which consist of a first unit for CO2 fixation followed by a second unit for precision fermentation toward customized SCPs. We discuss the design principles of the system, review current efforts to convert CO2 using natural and engineered autotrophs, and outline the potential of yeast for customized SCP production. Finally, we underscore the critical role of nitrogen sources for efficient SCP production.