Bioengineered formatotrophic E.Coli can be utilized to efficiently generate biomass from electricity. A popular direction for cleantech in recent years is that of biorefineries, that use living organisms to supply the human demand for chemical commodities. Electricity is considered to be a potential feedstock for biorefineries, with the end products serving as solid or liquid storage of energy. Such microbial electrosynthesis is highly dependent on mediators to enable electron transfer from an electrode to a living cell.
Formic acid (formate) is an electron mediator with a number of desired features for microbial electrosynthesis. However, wild-type organisms that can grow on formate are not suitable for industrial use due to slow growth rates and metabolism.
Researchers at the Weizmann Institute have successfully engineered a formatotrophic E.coli. By combining systematical analysis with computational tools they screened numerous metabolic pathways and identified the optimized metabolic pathway that supports efficient formate-based growth. This innovative method enables the design of industrial strains of bacteria capable of efficient microbial electrosynthesis.
- Biofuel and chemical commodities production.
- Efficient and robust storage of electrical energy.
- Cost effective conversion of C1 compounds into sugars.
By engineering E. coli, the workhorse bacteria used in biotechnology and enabling its growth on formate, researches at Dr. Ron Milos lab paved the way for efficient microbial electrosynthesis. The Researches started by investigating many metabolic pathways in order to discover how a model organism such as E.coli can be engineered for formatotrophic growth. estimate which pathway is most suitable to support growth on formate each pathway was examined based on various criteria such as biomass yield, thermodynamic favorability, chemical motive force, kinetics and additional practical challenges.
One short favorable pathway was consistently identified, that is the reductive glycine pathway. Furthermore. Researches generated an isolated organism that is able to convert formate to pyruvate or glycerate.