Integrating Carbohydrate and C1 Utilization for Chemicals Production

In the face of increasing mobility and energy demand, as well as the mitigation of climate change, the development of sustainable and environmentally friendly alternatives to fossil fuels will be one of the most important tasks facing humankind in the coming years. In order to initiate the transition from a petroleum-based economy to a new, greener future, biofuels and synthetic fuels have great potential as they can be adapted to already common processes. Thereby, especially synthetic fuels from CO2 and renewable energies are seen as the next big step for a sustainable and ecological life. In our study, we directly address the sustainable production of the most common biofuel, ethanol, and the highly interesting next-generation biofuel, isobutanol, from methanol and xylose, which are directly derivable from CO2 and lignocellulosic waste streams, respectively, such integrating synthetic fuel and biofuel production. After enzyme and reaction optimization, we succeeded in producing either 3 g L-1 ethanol or 2 g L-1 isobutanol from 7.5 g L-1 xylose and 1.6 g L-1 methanol. In our cell-free enzyme system, C1-compounds are efficiently combined and fixed by the key enzyme transketolase and converted to the intermediate pyruvate. This opens the way for a hybrid production of biofuels, platform chemicals and fine chemicals from CO2 and lignocellulosic waste streams as alternative to conventional routes depending solely either on CO2 or sugars.

Automated summary

Facing increasing mobility, energy demand, and the need to mitigate climate change, developing sustainable and eco-friendly alternatives to fossil fuels is a crucial task for humanity. Biofuels and synthetic fuels show great potential as they can be integrated into existing processes, with synthetic fuels from CO2 and renewable energies being considered the next big step towards a sustainable and ecological future. In our study, we focus on the sustainable production of ethanol and isobutanol, two common biofuels, using methanol and xylose derived from CO2 and lignocellulosic waste streams. Through enzyme and reaction optimization, we successfully produced ethanol or isobutanol from xylose and methanol. Our research opens up the possibility of hybrid production of biofuels and chemicals from CO2 and lignocellulosic waste streams, providing an alternative to conventional routes that rely solely on CO2 or sugars.