A study led by a team of researchers from the Weizmann Institute of Science in Israel has confirmed a recently developed fully autotrophic E.coli strain whose generated biomass is solely derived from a greenhouse gas.
E. coli bacteria cells. Source: Livescience
CO2 accumulates in our atmosphere and it is commonly used by plants to generate sugars for their sustainable growth.This promising strain could be used as a renewable food source and energy storage.
Hacking Metabolism
An originally heterotrophic bacterium was successfully converted into an autotrophic organism. Scientists rewired their core metabolic pathway, introduced heterologous (non-native) genes and Formate as an accessible electron donor, providing such organism with the required enzymatic machinery to effectively convert inorganic carbon into biomass under physiological conditions. Furthermore, the carbon source of nearly all biomass produced was confirmed to atmospheric CO2 with isotopic labeling techniques.
Summary of photosynthetic pathway from an engineered bacterium cell. Source: Cell
Photosynthesis is a process common to plants and some microorganisms, and it is the first step in the food chain. Evolutionarily speaking, this transformation is considered a major accomplishment since these two metabolic pathways are very distinct. Autotrophs and heterotrophs diverged millions of years ago, although some organisms with both metabolic routes are known to exist.
Summary of transformation. Source: technologyandus.com
Next Steps
Regulation of CO2 in our atmosphere has become one of the most important challenges in today’s era. We are constantly looking for sustainable ways of producing food, fuel and biochemicals, and this study presents a new yet promising approach to reduced carbon emitting food sources with a broad spectrum of fields in which this technology can be applied.
There is great diversity in the compounds that can be synthesized through this process and its deep understanding may have a large impact in the future of a new carbon neutral world.
This finding also denotes the flexibility of metabolic processes to support life as mentioned by the authors:
– “This rapid trophic mode transformation showcases the outstanding plasticity of metabolism and demonstrates the power of the framework described here for designing and implementing the rewiring of cellular metabolism.”
-Aron Engelhard
